Why not do a fundraising event for The Karuna Trust and get your friends, family and colleagues involved too. You can do any kind of fundraising activity you want.
You can use JustGiving to setup your fundraising page and help you along. Your friends just go to your JustGiving page and donate with their credit or debit card and the funds are transferred to Karuna automatically.
So please hop along to JustGiving now to set up your fundraising page.