I cut mine into fours, LOL! I just feel like it's neater that way.
But to answer the question--I usually cut rectangles then squares unless it's for DS, who likes to ask for something different every time just to keep me on my toes. He asked me to cut a sandwich into tenths once. He clearly thought I would balk at that, but he was wrong. He got 10 tiny pieces of sandwich and never asked for that again.