Usually I employ several techniques when Im working on a procedure, especially when Im tattooing an areola. This is a 4 year faded case when the initial goal  had started more of a tan soft color.  

My client wanted more pink so I incorporated a couple different pink tones over the existing color trying to create some texture variations with color. Since the color had faded and was rather flat, the pinks showed up over the top.

 I find that If the previous ink color isn't too dark,  tattooing over it turns out nice for  both areolas, brows and lips and even eyes.  The new ink, instead of finding its placement in the skin has  some type of  substrate (previous ink) to "grab".  

The pixel technique, that leaves open color space, is quite effective over previous color and it also lets the previous color glow through.  I used a 3RL instead of a 1RL. so that I could get in more color and see more texture from the...