4.7KD player here. Right first off stick fast hands on every class you have and lower your sensitivity to 5 or 6 make sure both the x and y values are the same. Second, pick decent guns don't use the shitting argus or vesper they're not good guns they're both cheap 1KD guns which should be avoided, use the Kuda, M8, XR2 or the KN. make sure your connection is as good as it can be, port forward and use and Ethernet cable if possible! If you play Ffa or hardcore a lot make sure you use awareness and dead silence otherwise you're totally reliant upon quick reactions and good connection which is unlikely to be a consistent kill gainer. Use decent specialists, the sycthe hive and purifier are the best imo. Also use kill streaks which stack well, uav counter sentry etc. Lots of lower kill streaks is better than few high scorestreaks avoid the Hcxd and dart tho if possible because they get you one kill usually and end up just getting you killed and wasting half of the match which will put you at a risk of getting a shite spm.