Knotts berry farm! help.?

I went to knotts for my birthday on Friday and it was a highly unplanned last minute 4 hour day there. I'm going again in 2wks for my sister's birthday and I want to plan it out better for me & her. what all should I bring to lessen my load? I didn't like lugging around my backpack when I last went & paying for a locker seems a bit much.