To start with you have two multiple choice tests. The first one is about all the information you were given. It helps to really know the material as it's never an obvious answer, a lot of them are similar. The second is the mental arithmetic. Again, a lot of the answers are very similar. I found going through a lot of the s/d/t questions linked on here helped me a great deal for this section.
If you've passed those two, then you do the diagramming and spatial awareness tests.