When you work on your breaking balls...do not become the breaking ball! I cannot tell whether or not you break up your sets with a fastball instead of throwing curveball after curveball...but essentially your body starts to adjust to the pitch in what you want it to do instead of just working on good mechanics with a different grip.
Do not become the pitch...you work on the grip with good mechanics. Mechanics are key to finding out what your true off speed pitches need to be instead of trying to mold pitches you like to your arsenal.
Just watch how you continuously keep falling more and more off after landing. This is a sign that you are becoming the pitch instead of working on the grip.
Another easy tip to remember when working on a breaking ball is to think of spinning it faster not throwing it hard.