Hi, firstly, if you are offering a full manicure, you should not be flooding any cuticle as all cuticle ie. non living tissue, should be gently removed. Not trying to be pedantic and I know many colleges do not teach the correct terminology but as you are in the process of qualifying, I thought I would just mention this.
I take it you mean that you are flooding the base of the nail so that the polish is in contact with the eponychium (protective skin fold at base of nail)?
Geeg does explain a very good method of applying polish. I refer to it as the 3 P's do placement of the polish 2 thirds of the way down the nail plate towards the base of the nail then push the polish towards the base to help off load some of the polish and stopping just short of the eponychium and then pulling away in the opposite direction to the free edge.
So place, push and pull. It is possible you are loading you brush with too much polish, hence the flooding.