I'm slim in general, rather thin. Do you know any methods to slim the cheeks down, that work? I have tried contouring but it just doesn't work for me. I don't know, maybe it's the lips? Do you recommend any brands that would sell something that makes the lips more pale?
Using a shade of foundation that's just a tad darker than your skintone works pretty well as a way to make your lips less pink, but also not like vampire one-skin tone. Dunno about slimming cheeks down, I wouldn't worry about it too much. cis guys have cute plump cheeks too. Making the lips a bit more neutral works wonders though! And making your eyebrows darker.
It depends on your facial structure and body fat. As you are already slim, it's probable that you do not have a naturally defined jawline. Nothing wrong with that though, as Ghostling said. Buy if you want to have a more angular face, you can try makeup as you suggested. I've never used it so I can't help you there. Another way I noticed is gaining muscle tends to help masculinize your appearance overall. There is not much muscle you can work in your face, but the neck and shoulders will make a big difference, as males have noticeably thicker muscles in those areas. Here are good exercises which hit your upper body, back, neck, and shoulders: > chin ups > pull ups > weighted shoulder shrugs > hang clean and press (with a barbell) > deadlift So that in combination with keeping lean and experimenting with makeup, certainly should make a difference.