The idea of jiu-jitsu is to give the little guy a chance to beat the big guy.
My number one recommendations for part time grapplers is: no alcohol - no smoking - Follow the Gracie diet. The reason I say that is because smoking and alcohol put a lot of effort on your body. Your lungs. Your liver. Your stomach. These things will make you suffer, man.
My strategy is not to give them a chance to hit me.
You put the Devil on the other side, and I will come to fight.
Talented people without discipline don't go anywhere.
A black belt only covers two inches of your ass. You have to cover the rest.