Nice kit you got there. I painted the Billiken kit a few years ago and mixed my own skin color from various old Humbrol water based paints I had lying around from when they still sold those in Denmark.
Here's a break-down of the paints used:
Matt white (about 30 %)
Matt Flesh (about 20-25 %)
Gold (about 43-48 %)
Matt red (about 2 % - be very careful not to add too much)
I know... GOLD... what's he thinking? But it gave a pretty good naturalistic shine to the skin tone. Used semi gloss cleacoat on top of that - big mistake - so I cannot show you exactly how it looked... but it was smooth looking. It looks good with the clearcoat too, though, a bit too "sweaty"-looking when taking pictures.
Never got around to painting the lip color as the color I had mixed unfortunately dried up and I never got around to mix a new batch, as I had used up all the gold and flesh color in the last mix... so, can't help you with that.
Eyes should be painted with a fine brush. Start with the white - use off-white or mix your own color - then paint the iris and pupil matt black, then use a light blue to paint the irish - don't worry about painting over the pupil, as you can always repaint that. Then a maybe paint a little light dot at one corner of the irish... and seal it with a coat of gloss clearcoat.
Then, remember to leave an edge of skin color around the eyes, when painting the matt black make-up around the eyes, to make it look more natural.
Don't worry too much about highlights and low-lights, as that tends to look fake, anyway, unless you know what you're doing.
