This is something, for me, that is a "hit or miss" proposition. Make sure that you have a good source of running water near by when you start. This is for local bleaching only. You can swab on the bleach or use one of those Chinese watercolor brushes.
I like to print the highlights a little veiled (read a little to dark) and then put the whole print back in the bleach (Farmers Reducer) for a little time. IF you like the look of the print, in my experience, you are too late.
Good luck! Tip: the question is like asking someone for directions to Carnegy Hall. The answer is "Practice Practice Practice.