Well, I can see how that would make it difficult. Layers and masks are very worth learning how to use, and it's pretty easy once you get the general concept of implementation. Up until a couple of weeks ago, I kept masks at a 10ft distance, myself. =) Ask me sometime, if you want to, and I'll illustrate the general concept of implementation. However, if you'd rather just work on a single layer (which I do 40% of the time) then I suggest the history brush tool as incredibly awesome.