If you are using the original skin colors already on a previously made sim you'll have to take them into Create-A-Sim, switch them to a normal skin tone, then change their outfit and then pick the color that they need with the update skin colors and the muscle definition will stick on them when you exit CAS. Otherwise if you are creating a fresh sim just select which ever color you want with the updated skin colors and go from there.
Please fully read all of this post and comments before asking any questions as you will find most of them already answered.
*They do not and will not replace any of your skin tones. If you are not using a mod to be able to view all of the skin tones then you will need to use the scroll button on your mouse or figure out how to scroll on your touch pad with your laptop.
*They are package files so there is no need/way to extract them. Just put them directly in after downloading them.
*These skins work perfectly with all expansions and stuff packs up to Pets and Outdoor living and will probably continue working perfectly fine with any other ones that come out.
Download Individual Files Here
Download All in 1 File
*Skin default replacements used in photo are from Club Crimsyn.*