In any preparation for the DAT it is important to continually evaluate your progress by reviewing past tests, and taking self-administered tests. In then end, your familiarity with the test format and style of questions can be as important as your knowledge. Both Princeton and Kapalan offer DAT preparation courses which offer many resources to you. The one major drawback is the expenses involved. But they can be very helpful, especially if you feel that some personal tutoring in certain areas will be of some help.
Self study is probably the most effective way to prepare.
It is certainly the least expensive. It however requires a high level of personal commitment, motivation, and diligence. If you choose this route it is important to set aside a scheduled, regular time to do your studying and stick to the schedule. This had a more wordy approach which was good in explaining the concepts being tested. It also gave good explanation to the correct answers.