Once you have a stabilizing grid down, it gets easier to quilt. If you have the 10 inch grid, then maybe 1.5 inches from that do another row on either side in both directions. You will get sort of a plaid or lattice effect, with still large untouched centers, yet within the quilting guidelines.
Good luck! My goal for these next few years is I am going to try to be better at the quilting down part of things but I can't draw and have a limited imagination when it comes to quilting designs.