I guess it depends what you consider "realistic". I usually go for a base coat chosen from a variety of light rust and light brown shades (Vallejo Panzer Aces Light Rust, which is akin to a slightly more reddish Bestial Brown), which then receive a very thin chocolate brown wash; once that is dry, I follow up with thinned-down skintones, usually VMC "Sunny Skin" with a dab of the base tone first, then VMC Sunny Skin pure, followed with light skin.
That said, I also tend to vary the different tones used for the different layers to give some variety. Here's a pic of a skin paintjob with which I am quite happy:
This is the very basic variant, i.e. light rust, brown wash, highlights with sunny skin+light rust, sunny skin, sunny skin+light skin, light skin. The important bit, as far as I am concerned, is getting the individual coats thin enough to blend into each other tonally, while not having it run into all the crevices. So that would be six steps, but since Vallejo colours dry quite quickly, if you practice assembly line painting as I do, you can get the figures done quite nicely in a short amount of time - the above had a net painting time of about an hour for 5 figures.