I know that many people will tell you not to get the ARCO, BARRONS, etc. books to study. On one hand this is correct, on the other hand it is not. For those of you who do not have a technical degree that requires a lot of math, you may have been out of practice for the last two years of your collegiate careers, so head my advice and start practicing. I was personally able to complete all questions in the arithmetic and math knowledge portions of the test, but it took a lot of practice.
The spatial aperception section didnt seem very difficult, they really dont try to trick you that much on this section. The rest of the test is much like this...the standard reading sections that you will remember from any standardized test. So if you are going to use ARCO, make sure you are using it for the practice sections that the book subscribes for the force that you are applying for be it the USAF, USMC, USN, etc. If you gt the Barrons book, dont worry about the word recognition, though I did add about 200 words to my vocabulary, not a total waste. Look through the mechanical knowledge section also, but most of this will in order to guide you principally. Make sure you pay attention to the Nautical terms, for those of you whose parents do not own a sailboat, this will be more difficult, just make sure that you have a general knowledge of what goes on in and around the ship, dont get too specific and you'll be fine I'm sure.
Time and effort will be the top reasons why people did well no the test. So practice, practice, practice, and you should be fine.
I put in a decent amount of work and wound up with a 7,7,7 67. Maybe not the best grades ever scored, but the key is that they are certainly good enough.
If you need any advice, feel free to write back.