Well I don't think you will have a set of guides that will apply to all games, because ultimately you will need to optimise for each game.
First, remember you can get a lot of information from each touch, so no need for invisible buttons you can just interrogate the screen vectors.
Second, many of the default touch functions like swipe and double tap take a few ticks to set and will also co trigger with many other touch commands so if you use these make sure your logic clearly discriminates.
I actually favour subtle on screen buttons (partial opacity) for discrete functions, like interact, or shoot etc. Allowing you to check touch is on button if in certain side of screen and if not move/walk your character for example. Walking could be lower 2 quarters of screen for example and jump in top of screen.
EDIT, forgot to say that once a touch has begun you can store and remember it, so for example, if you touch screen left and the character walks left, but then slide your finger right the player can turn around and track it.