Labbing's a fancy word for practice. For labbing O, go to practice mode with 2 controllers, set the Raiders up on D. Run your offensive plays against different coverages and heat/F@G D. Then use random play. Practice your protection schemes, reads, etc.
It's the same with D, although after practicing the setups I've found it more beneficial to play a friend or and unranked game.
I hope this helps.