I didn't take a course and studied on my own. I used
Helping Individuals and Businesses Navigate Drone Law, 3DR's sample quizzes, FAA downloads (in particular their study guide), assorted sectional downloads, and plenty of Googling. I kept taking the quizzes over and over until I consistently could get in the high 90% range. Although I have no idea what your test may have on it specifically, I would know at a minimum the following:
Sectional charts, their legends, and how to read them.
Airspace classification and how it reads on a sectional chart.
METAR (weather) abbreviations and how to read them.
Impacts of weather on flying
Aeronautical Decision Making and Judgement.
Know the abbreviations (I made flash cards).
I actually enjoyed studying for the test and I learned a great deal. It seemed overwhelming at first, but going through the quizzes and researching my wrong answers until I really understood how to get the right answer got me through the test. (And I learned a ton of stuff which has already proven helpful!)
I had great success on the actual test. I took my time and still had 33% of my allotted time left over to review my answers (which I did). I booked the test and gave
myself about 10 days/2 weeks to study. I hit it hard (6 hours a day) for the last 2 or 3 days before the test.
Good Luck and Happy Flying!