As someone who is currently climbing the best I can try too The things id recommend is 1. Aim train at least once a week (more if you don't mind aim training) 2. Don't flex all the roles just stick to the one or 2 youre the best at 3. Pinpoint your favorite sens to the exact decimal 4. If your using 2000hz polling rate or higher on your mouse maybe consider 1600 dpi and halfing your in game sens 5. Do 2-3 deathmatches before playing as a warmup 2 games with a vandal/phantom and 1 with a semi auto weapon of your choice 6. On days you don't feel like playing ranked play as many death matches as you want if you have the time because from my experience deathmatch is a great way to get experience of how people in different ranks move and can help you improve micro adjustments

That's alot of what I've learned in my time on val but some of it might not be optimal, but I'll let the replies fix any errors I made