There’s good advice from CF on the site about how to run the 200, try a search. I advocate coming out of the blocks fast but not quite as agressive as in the 100m in order to prolong the acceleration a bit. Its a case of maintenance after that, no sudden surges off the bend (injury risk) focus on arm action up the straight.
Re the training, you can still advance speed by running sub max, and it will keep you fresh.