As many as 16 bands will perform at 12-hour charity event Rock for Ukraine at the Corporation Club on Good Friday, April 15.
Craft stalls, food and face paints will also be on offer, while the winners of a raffle will be announced in a live stream a few days later.
He had initially planned the event as a small open mic night – but was soon overwhelmed with requests from bands who were keen to show their support.
"Like everyone else, the news has been upsetting me and I just thought what can I do for all these poor people,” said Colin.
"I thought I’d put a little open mic night on and maybe raise a few hundred pounds, but now, within 10 hours, I’ve had 12 bands asking me to play. Now I’m having to turn down people, because we’re full from 12 o’clock till 2 in the morning.”
Colin, from the Hart Lane area of the town, added: “Now it’s going to be a full one day festival with 16 bands on. It’s gone really big all of a sudden.
"It’s really taken off.”
Bands performing include The Full Timers, Fizzy Fish and The Strawberry Mynde.
Colin will also take to the stage with his band The Dead Heroines, where he plays the guitar.
Speaking of the support shown for the event so far, the former English Martyrs pupil said: "It’s a bit overwhelming and emotional actually.
"Hopefully it will be a really great day for people.
"It’s gone from an open mic night to an all day festival like Glastonbury in the Corporation Club.”
Proceeds from the event will be split equally between Oxfam and Unicef.
Colin, who works as a plumber, added: "I’m just overwhelmed with the kindness and support.
"Hopefully we’ll raise as much money as we can.”
Tickets are priced at £6 for a half day or £10 for a full day and can be purchased online at skiddle.com by searching Rock for Ukraine.