Like many SNDers have said, practice is the best way to get higher scores. Some are naturally gifted is special reasoning and can easily see the shapes from different sides and easily see the hole punch paper unfolded.
Regardless, special reasoning is easily trained. By doing as much examples as possible you will train your brain to recognize patters and will get higher PAT scores. That said, you also must spend time reviewing the answers both wrong and right choices.
Kaplan blue book has great example but it is a little easier then the real test so I suggest starting with it to build up your confidence and get familiar with the test. Then move on to Topscore and finally DATachiever (this one is hard, but great practice!)
If you want even more practice for free, start picturing in your head or even drawing how everyday shapes look from different sides and what keyhole they would be able to fit. Look at your TV, Xbox, shampoo bottle, etc and predict their views from different sides. This too help a lot.
Also, the cube counting should be the easiest section and you should be getting 15/15 every time. Kaplan and Barron suggest great strategies. I would make a chart and counted all the cubes before answering the question. After doing all the tabulations I make sure all the #'s add up and easily do the questions.
For hole punching, try taking square pieces if paper and follow the question in terms of folding and then make the appropriate holes then slowly unfold the paper and try predicting as you go along. You will train your brain to quickly see the patters and will be a pro in no time. This method is also great because it's free! (minus the cost of paper).
Good luck and hope this helps!