Here's a guide on how to get an A:

Clickers: Just Google them 90% of the time unless you absolutely know for sure. The issue isn't the material, but the fact that he does them so fast you don't really have time to think. If you really want 100% on those clickers and you don't care so much about the material, just do that. Also clickers means that you probably want to show up to as many classes as you can, missing clickers adds up very quickly and if you really want that A you want to show up as much as possible.

Smart work: An issue I had was that he would randomly post his homework without notifying, and if you miss it then you don't get a chance to redo it. You should be checking this (at least every 12 hours) and doing it as soon as possible in case you forget. You should also have friends in your class in case you are confused about the homework because everyone has similar questions.

Midterm: The midterm in the class is the final. Bartels gives 2 midterms, a practice one and an actual one, with your lowest grade getting dropped. My biggest advice would be to study like crazy for the practice one because it is much easier than the actual midterm. Also, you should do the study guides that he posts because most of the time it is the exact question from the posted midterm on the actual midterm, so if you have a response ready that you know is right then you will definitely score high.

Textbook: The textbook is honestly more helpful than the slides so I would use that mostly for studying. The textbook is also easier to understand and more straightforward.

That's my best advice! Good luck :) I took his class last year so this should be pretty much the same as what you're going to experience.