Adding sheer effects can be a cool addition to your female figures. Here is the way I do it and hope it can help you to add this neat effect to any of your figures.
The figure I am using is a female elf from El Viejo Dragon. I start by painting her skin in the normal fashion so I will know my tones of skin to use in the sheer cloth. Here are the colors I use for her skin and will include them to create the sheer look on her clothes.
After the skin is done I start adding the colors of her clothes on the high parts of the folds only. This is to show where the skin colors will be on the clothes that are closest to her skin.
Here are the colors I used for her clothes, these don't matter and can be applied to whatever color you are using. It is just to show that my first step is to mix some skin tone with the base for my clotes.
here is the green with flesh applied for step 1.
step 2 I keep adding more flesh to the mix until I am almost using straight flesh. You want to use a darker tone of your flesh not your lighter tone. The thin cloth still changes the color of the skin, the thinner her clothes the more like her flesh it will look. I want it really thin on her breasts. You can see I have also painted her nipples.
You can see how it is developing. I have worked more on her right breast than the left one. You can see here the difference and what you are going for.
I keep adding my thin layers until I am satisfied with the appearance of her clothes.
Since her clothing appears to be all the same material I have to make the head covering sheer as well. I've never painted sheer material to show hair before so this is a first. It still needs some work but it does show any part of the figures clothes can be sheer.
Here is the sheer finished to my satisfaction. It was getting late so my light color has changed, that is why she looks warmer.
I hope this shows how simple this cool effect is to pull off. It does take a little practice but after using it on a couple of figures you will be a pro. Now, go dig those girl figures out and give it a go.