It always comes down to practice. First of all, train your map awareness. By knowning maps, you would improve because you know where to position yourself according to the situation. Muscle memory really helps, practicing dm, aim maps, etc, you would get used to placing your crosshair head level and able to pratice your flicks which is useful in situations where the enemy catches you off guard. Know your weapon's recoil patterns. Mentality. Mentality is another key factor in how you perform. Try your best not to start tilting if youre losing, always focus on winning and if you lose? Always keep a positive mindset, if you cant, take a break. Being positive to your teammates is important as well. If your teammates are doing bad, always give them confidence it helps alot because they may be having a bad day/game. CSGO at the end of the day, is a team game.

I was GE but currently unranked due to not playing for a month because of exams.

One last thing to note. Gear does make you better (it also depends on the person taking advantage of the gear)  whether someone says otherwise, 144hz monitor will always be better than 60hz. Having a good mouse will help, but not so much for keyboards. Good headphones would not help significantly, but it does help.

Sorry for the long wall of text and not properly formatting.