The main tip that Kaplan gives for TFE is that the lines in one are related to the lines in another. That said, all of the vertical lines in top will be shown as vertical in front, all of the horizontal lines shown in front will be shown as horizontal in end, and any vertical lines in end will be horizontal lines in top (I think that's right). So one easy way to get rid of a few answers is to count the number of horizontal and vertical lines that SHOULD be in your answer, and then compare that to the choices given.
An example, say the end image is unknown, the top image has 5 horizontal lines, and the front image has 4 horizontal lines, so you then know that your answer must have 5 vertical lines and 4 horizontal lines. Get rid of any of the choices that don't match that, and then just try to picture the object. After you get rid of the ones that don't match the line numbers are usually just different in the line being visable or not.
Also, one easy thing that messed me up when I first started looking at these, and you probably already know this, but just in case, END is from the RIGHT of the object.
I hope this helps!
