Mouse cursor placement is essential for improving accuracy with faster reaction times, preemptively placing the crosshair at head height or where you expect the enemy to be before they peak reduces the distance your mouse has to travel before firing. Comfortable hardware such as a well-calibrated gaming mouse or a +120 Hz monitor can also improve reaction times. Mechanical skill aside, improving game sense is sometimes an understated consideration that can make a dramatic difference for overall performance by paying attention to things like common player paths for prediciting enemy movement, listening carefully to footsteps and audio positioning, effectively using smoke gernades for cover, knowing how to rush a point with your teammates and which angles to cover, rotating at the right moments, and anything else that can improve your chances for success in terms of strategy. Most of these principles will become obvious with continuous play and experience.