You could use a few spare moments to jot down some sort of outline to the letter you want to write, or to use Google to see if there is already a charity set in place to provide blankets to which you could donate your time or money, or suggest in your letter that money be raised to donate to a charity already in existence.

www.projectlinus.org sprung to mind when I saw your post (I’m not affiliated with that charity in any way).