i use the dipping in water trick as well. also i have found depending on the level of irritation you are going for (lets say you want that same redness around it as when the tattoo is first finished) i will use a pink and a red and dilute the crap out of it haha. for me 2 drops of a light red in a #16 cap makes for a nice irritation redness. but be careful too much red and it will look fake