your coach should prepare you completly for tournaments.
mainly you have to know that gound-time in judo is very limited. you have to make obvious progress to a pin or sub every 5 seconds as a rule of thumb. if there is any real pause, if you cannot pass his guard completly, or if you are unable to finish the armlock/choke the referee will stand you up.
you cannot do guard-flops. you cannot make poor attacks just in hopes of getting to the ground. you do NOT have to do ground-fighting-- you can just get up or stall out without penalty.
flying armlocks and chokes are okay, but standing chokes and armlocks must be done extremely carefully (opponent must go to knees before you. you cannot throw an opponent while applying a standing choke or armlock.
neckcranks, leglocks, wristlocks.. all ILLEGAL. cannot put your hands/feet/etc in the face either... cannot bend the spine either.
hope that helps.