Holy hell ... this is STILL going on? I've been gone for more than a week now ... I figured SE would have at least done something. Even a public service announcement ... anything?
As for you, I feel your pain. Since SE has decided that cooperation is not in the spirit of team oriented gameplay, coming to the forums is probably your best bet. Without knowing specifically which tank you play as, the best general advice we can give you is to never, EVER, pick up more than 4 stacks of medals. Sometimes you can get away with more in 8v8, but if you get more than 5, you had better amscray ASAP. Find a corner and suck your thumb for a bit. After that, it's about knowing what your specific role can do, and doing it. If you have any specific questions about a specific tank, it would be a good idea to ask them or post your own thread topic. You'll usually you'll get an answer from someone who's been around the block.