I like to first of all, write down ideas when I have them. That way I have something to draw on. I get a lot of good ideas in comments around here. When we are meming back and forth it gets the creativity all stirred up. If you are out and about and you see something that makes a funny thought pop up, take a pic of whatever it is, or try to find an equivalent image in a search. Add the caption of whatever funny thought you had. Stuff like that you know.