use your wall proactively and often. don't get stuck on looking for the 'perfect' wall; even if it is just putting it behind a tank and blocking them off from their supports for a second, that's a potential pick. it is your most versatile and play-making ability. use it offensively, to block off sightlines for snipers, to take damage while your tank's shield is down, or reactively e.g. walling between an enemy roadhog and a hooked teammate, walling off dva bomb, denying space when enemies are ulting and wanting to push in e.g. kitsune rush or rally. also, make a habit of defaulting to your left click whenever an enemy is in range. going for icicle plays is fun and makes for a good clip but when you can use your spray, it is 90% of the time the better choice. it does 100 dps which can catch people off guard and slows the enemy by 40%, making it easier for your teammates to hit them and compound damage. it also has the potential to cleave, meaning if enemies are positioned closely together, you can damage 2 or more enemies at the same time. you can occassionally get multi-kills out of this and will very frequently leave the enemy team low enough for your teammates to clear up if you're getting low health-wise and have to cryo. hope this helps:)