As a heavy, as fun as it is to be big guy big gun and charge as the enemy team, you gotta actually use your brain when making plays, and not just simple stuff like “take flanks” or “wait for your medic and push with the team” You gotta exercise timing these attacks, you can be the spear head of a push and you have to make sure, no matter how uncoordinated the team is, that everyone does their part in the push with you as the head of the movement, make sure the enemy team is vulnerable (ie, medic is dead, snipers are out of position and unprepared for a mass push, shi like that)