It's Red Nose Day this Friday. A galaxy of British comedy talent will be joining together to encourage everyone to support Comic Relief's charity endeavours.

Sir Lenny Henry, who is a Trustee of the charity and has been hosting the show ever since it launched on TV in 1988, will be on screens again this Friday to open this year's proceedings, which will be broadcast live from a special studio at The O2 in London.

Stand-ups Luisa Omielan and Rob Beckett and actors Warwick Davis and Sally Phillips will be amongst those taking on presenting duties during the evening. Elsewhere in the studio, Joe Lycett will be helping to run a busy pizza restaurant.

Whilst the news is on BBC One, Greg Davies will be taking over hosting duties on BBC Two from the top of The O2. Comic Relief warn: "All will be revealed, quite literally, from 10pm". Meanwhile, the late evening's entertainment includes an hour of comedy performances, introduced by Russell Brand.

We hear from these presenters below...

What is your favourite Comic Relief memory?

Lenny Henry: There are quite a few actually, I find it very difficult to choose. Popstars with Rowan Atkinson and various people was great. I have to say, having spent a lot of time in Africa, the one fantastic moment was when we went there with Ewan McGregor just before he was about to do Star Wars and we spent a lot of time in the car singing. He's a really good singer and there were nine-part harmonies which weren't bad, I reckon we could have gone on Let It Shine and won!

Luisa Omielan: When I was at school and we used to make things to sell, like a cake sale, and one thing we made was Rocky Road. But we weren't very good, so we used to just get loads of melted chocolate and marshmallows and mix it all together. It tasted disgusting but we used to sell it for 50p a pop. I loved every year that we would get to make really bad Rocky Road! On the show itself, I loved anything with The Vicar Of Dibley - the one where she met Johnny Depp and where they had the party and the electrics went out and they were like, "oh Madonna's here" and "oh the Duchess of York is here" - I just thought it was so funny.

Greg Davies: I've never done Comic Relief before this. I mean, obviously when I was a teacher we got involved with Comic Relief things at school. Oh, I did The Inbetweeners Rude Road Trip a few years ago. I was briefly in that - I was on the phone on the road trip giving the boys hassle.

Warwick Davis: When I think of Comic Relief I always think of Steve Coogan's contribution to the shows as Alan Partridge, he's one of my favourite characters. I remember he hosted from BBC Radio Norwich doing a simulcast. To him [Alan], it was like the latest technology that he was able to broadcast on TV and be on radio at the same time but the whole evening kind of culminated with him doing a finale of a Kate Bush medley, which was fabulous. There are so many though, and you look at who's given their time to Comic Relief over the years and the very best of British and international comic talent has given their time to do a sketches - it's fantastic, the spirit of the whole thing is what makes Comic Relief so special and so unique, so that for me is a real highlight.

Rob Beckett: Years ago I wrapped all my mate's bedroom up in tin foil and it's on YouTube still. If you type 'you've been foiled' into YouTube it's me about ten years ago and we wrapped his whole bedroom up when he was away on holiday, and then he come home and we filmed his reaction. It was for Comic Relief, so me and my mates all did it and he didn't complain. It took ages to unwrap it all, but that was fun - it was a good prank.

Joe Lycett: My favourite skit from watching the show on TV was when the Beckhams were interviewed by Ali G, that was great. When I was at school I dyed my hair red for Comic Relief. The deputy head teacher took me into his office and told me that it wasn't allowed though, so I had to go and wash it out. Though, because I am blonde, my hair went ginger so I stayed ginger for the rest of the day.

Sally Philips: I've always loved Miranda Richardson's Jane Austen sketch, it was a really long time ago but she was so brilliantly dead-pan, it was really, really funny. For Sport Relief I auctioned myself for marriage for about £2,000 - it didn't go well, there were no takers! But then I did attend a Comic Relief wedding one year, there were two people who got married for Comic Relief. I don't know if they're still together.

Russell Brand: When I was a kid and Comic Relief was on it seemed really chaotic and like mad things were going to happen. I liked it when Billy Connolly was running around in the nude. I remember watching Sir Lenny Henry in the very early days in lairy suits and really enjoying that. I remember Rowan Atkinson doing his school headmaster sketch for Comic Relief where he did all of the different names when he did the register. I think fundraising stuff went on at our school but I wasn't really a joiner in at school so I don't remember ever having to be in a bath of beans or gunk. I do remember thinking "ah this isn't proper school any more, that's good" - it was sort of a side step from bunking off.

There will be lots of comedy on TV this Friday. What are you most looking forward to?

Lenny: I'm looking forward to all of it. It's going to be brilliant. Graham Norton's going to have the longest chat show sofa in existence, and I want to see how they get it in the building, I'm fascinated! Greg Davies is going to be in a hot-tub on the roof of The O2 - that's going to be good - and Ed Sheeran might be around too. That's a secret... but if you see a ginger geezer with a big anorak on, I'm betting it's him. I think it's going to be a fantastic night. I always enjoy it, the 'live-ness' and the fact that it's a bunch of comedians running around being anarchic! Also, Russell Brand is going to be doing stand-up on the night, I really, really get on well with Russell so we'll have a good time.

Luisa: To be honest, hosting it and being part of the team - but mainly just the shambolic-ness of it. I'm excited to be part of live TV and there are so many fantastic people working on it, it's a real privilege to be part of such a team. I'm looking forward to the shambles it is going to become! I can't wait. I think we're going to have so much fun and hopefully the audience at home will feel that too and they'll all donate.

Sally: I'm looking forward to Love Actually. It's pretty amazing that those people have all become gigantic stars. I'm quite looking forward to Joe Lycett and Johnny Vegas's pizza restaurant too.

Greg: I'm looking forward to being on top of the O2 in a hot-tub - it feels like my rightful place. I don't even mind if it rains; I'll be in a hot tub - it'll add to the romance of it!

Joe: I'm looking forward to the anarchy and just how anarchic we can make it. My main goal is to see how bonkers it will be. Running a pizza restaurant will also be good, as then I will be able to tell my parents I have finally done a proper job.

Rob: I think I might be in a hot tub with Greg Davies - spoiler alert! - but that will be quite good fun. I'm looking forward to raising money. It's just fun doing something I watched as a kid.

Russell: I'm looking forward to hosting this bit that I'm hosting because there will be lots of new acts and apparently I'm going to walk around and talk simultaneously in the studio - a challenge for anyone.

Warwick: I'm going to be onset with Catherine Tate again, the wonderful Catherine Tate. I absolutely adore her she's so brilliant so that will be quite nice. But that will be a live element, which again will be interesting.

Are you looking forward to presenting in front of a live audience?

Luisa: I'm really looking forward to it - I'll be doing some stand-up as well, so hopefully it won't feel too alien, hopefully it will feel quite intimate and fun. I feel like we miss that 90s style of television where it was live and raucous, and so I'm quite excited about bringing it back.

Lenny: Well, this is something I've been doing since I was 16, so the idea of looking forward to it is really something quite odd. But yes, I'm looking forward to Comic Relief this year. It's going to be brilliant, it's going to be exciting and passionate and the films are going to be moving. I know what my bits are, I just don't know what anybody else is doing. As my nephew would say, it's gonna be dope! It might even be super mega dope!

Warwick: For me, I just think you get such spontaneity out of doing something live. If you know it's recorded - and most of my work is in the recorded genre, as in films and TV where you get a chance to do take two - it makes you a little bit complacent as a performer because you think "oh I'll have a go". But when something's live there's an energy to it, a spontaneity and you never know what's going to happen! I think the audiences respond to that and, as performers, we all respond to that and the whole show will have this fabulous energy.

Do you feel honoured to be part of it, or is there a touch of nervousness?

Rob: Both really. It's amazing to do Comic Relief, because I watched it as a kid with all my family so to be doing it just feels surreal and weird so there's a bit of nerves that I do it alright but it should be alright, and you know, what could go wrong?! I might say a word wrong on the autocue, but no one cares do they?

Sally: I've never done any presenting before - I'm going to be a car crash! Ha ha!

The show is live for the first time ever from a comedy club environment so there is a danger there might be an anarchic feel to things, is that a good thing or a bad thing?

Russell: I think that will be brilliant. I will be nervous, but I think it will be thoroughly enjoyable.

Joe: It's a good thing, a lot of telly has gotten very formulaic and you can predict what's coming up. My favourite telly is when something goes off script. I did Sunday Brunch with Bradley Walsh a while ago and he completely took over, he did stuff like taking an ingredient across the kitchen and he just walked around where the cameras were. It's a perfectly reasonable way to walk around that room but it completely changed the dynamic of the studio space. Stuff like that is a really simple way of doing things but will keep the producers on their toes! I think it's brilliant but I'll be absolutely petrified!

Sally: I've never done any presenting before - I'm going to be a car crash! Ha ha!

Have you got any kind of pre-show routine you do before going on stage?

Lenny: Apart from oiling up and wrestling with various members of my family in a loin cloth, no!

Luisa: I take like an hour just to do my make-up and hair, I just like to take time, listen to some music and get in the mood... and get zoned up and get revved up. I'm a bit nervous though, because you've seen the names involved and it's a bit daunting! But hopefully it will be fun.

Warwick: For me, it's always my left shoe on first then my right one but it is only when I'm performing. When I'm going out it doesn't matter but if I'm going on stage or on TV it has to be that way.

Rob: Yeah, I burn a lot of fossil fuels [laughs]. No not really. I just have a shower and go to work.

Brand: Yes I do, I quieten myself right down and try and think about giving people a thoroughly entertaining time, usually in the lavvie. No superstitions like footballer superstitions, but rituals which are the sort of bed fellows of superstition or the more sacred. Well a sacred superstition is a ritual but they're not things like 'turn around three times and balance something on my head', it's all just making sure I'm lined up.

Sally: I think I run around in terror!

Greg: I will be having a pre-hot tub ritual; and that will be to remove every single article of clothing - everything! So, whatever you see on BBC Two, know that I will be fully naked. I am committed to this, and I think I'll be the first person to be fully naked on top of The O2 so I shall be breaking records as well. I've never been more ready, I don't feel remotely nervous. I feel pumped.