As this is my first post on this site I would like to say thank you for all of the information that everyone has put on here. I took the full ASTB for the first time two days ago and had only two weeks to study for it. The gouges and other sources of information that I found on here were invaluable to me.
The majority of what I studied was the Barron's Military Flight Aptitude Test study book (easy to find and Barnes and Noble) I found it to be extremely helpful and would recommend it to anyone who is planning to take the test. From this site I was directed to the ARCO study guide which you can download online for free, atrickpay's guide, and a host of other small guides that I found just exploring the various ASTB threads.
As a quick and dirty breakdown of the test I'll go through it section by section, I took form 5.
Math- this section is easier than I was expecting, coming from a Political Science degree and only a few calculus classes I was the most worried about this section the most. The Barron's book adequately prepared me for the types of questions that were on here, lots of basic algebra with a few word problems. I remember specifically a few questions that were of the (car A leaves and travels at 45 mph and car B leaves and travels at 65 mph) type, so study those and do plenty of practice examples, I found some good examples on the NOMI website and in their practice questions.
Reading- For me this was the easiest of the OAR sections, I finished and had time to go back over every single question again. My advice is just practice these in a timed environment so you don't run short.
Mechanical- Again the Barron's book was a great example of how this section would be. There were lever questions, rope and pulley questions, mechanical gear advantage questions, and the water tower example. I did not have any compressed fluids questions on my test form. What I struggled with most were the rope and pulley questions, I studied them a TON over the two weeks that I was preparing and still had some trouble. Maybe this is just me having issues with that particular concept, but I would advise anyone to know it well as there were several questions in this section regarding it.
Spatial Apperception- As with what everyone on this site has said, this portion is harder in the test than in any of the study guides. There are crazy angles and the situations presented were often more complicated than anything I had seen beforehand, the only thing I can say to do is practice over and over, find any possible practice questions and do them.
Aviation and Nautical Info- I read on an earlier thread someone's post "live by the gouge, die by the gouge" for this section it is true, you can gain the greatest advantage here by just putting your nose to the book and studying. Know the structure of a plane, which control surfaces control what movements, the instrument panel in detail (the big 6) and know basic weather fronts. I had one random question about clouds here as well.
Aviation supplemental- I expected this section to be easy as it is supposed to be a conglomeration of all the sections, but on my test form it ended up being nothing but an extra Aviation and Nautical Info section. I had no math, no mechanics, no reading, and no spatial apperception. I will be the first to say this was a HARD section on form 5. The questions were random and asked from a variety of concepts. Make sure you know aircraft instruments and what they do, study binary numbers (I was asked what specific numbers were in binary form and had no idea) Also know what a Radio Magnetic Indicator is and what it does.
Sorry for the long post and any grammar errors, I hope this provides a little insight to my test form for anyone who is about to take the test.I'm happy to answer any questions.
I scored- 7/8/8/53