If I got really stuck with something, I cut out a piece of paper and folded it so that my brain could get of the 3D nature of what I was looking at. I know it sounds tedious, but just going through the process really helped me get an idea for how to fold things. Also, I used Crack the DAT PAT. Repeating the process so many times that basically there was nothing new they could throw at me. It helps to do a lot of practice because then you have a voice in the back of your head saying "I know how to do this, I'm just struggling a little bit". Once you learn that struggling with a question isn't a death sentence to your mark, you end up doing a lot better. Just my two cents.