I am glad you are giving the ACT a try. It may turn out to be the better test for you.
Use this last week before the test to become familiar with the format of the ACT.
If your schedule allows, take two real ACT tests, in a timed setting. You can do two sections a night.
Review only what you get wrong and learn from those mistakes.
Timing is very critical on the ACT so you need to get that down.