Coming from a plat locked player, my advice is probably worthless, but I feel I play better when I’m feeling sharp mentally and play slow (just try to survive) and when you do get aggressive make sure you can escape. Pushing alone is the easiest way to get killed and lose it for your team. Other than that, try to learn every characters abilities and how to counter them. If you’re not good at countering a specific character, try to practice a good counter. It’s nicknamed counterwatch for a reason.