Tutorial : How to convert an Alpha skintone to an Overlay so it can be used for your Maxis Match/Mixed sims

Hello, due to popular demand, I just decided to make a tutorial for this. It's really easy to do so if you're not a modder, don't worry!

What you need : 

Sims 4 Studio

GIMP or anything that can modify a .png file properly

A .package file with the skintone you want to modify

(I will use a skintone made by Golyhawhaw as example)

1. Make a backup of the .package file with the skintone you want to modify. Open the .package with S4studio, using the "My Project" big button.

2. Click on Diffuse, then export. You will export the skintone diffuse texture as a .png file. Name it as you want, I named it "test" for this tutorial. DO NOT CLOSE S4STUDIO.

3. Open GIMP. I personally use GIMP v2 in French, but even if it's in french I will explain to you in english.
Drag and drop the .png with the diffuse texture you just exported from S4studio on GIMP. Then, on the color tab, play with the options you have : Your goal is to make the skintone gray.

4. Your skintone should looks like this (without the writting, sorry but I have to) :

4.2. You can change the contrast. More contrast will add more details to your skintone as overlay in game. 

5. Now, you have to export your work. Click on export from File or SHIFT+CTRL+E.

5.2. You can change the compression level value if you want, I personally make it to 0 so there is no compression. Then click on export. If they ask you to replace the original file, say yes.

6. Go back to S4Studio, you should now import the grey skintone diffuse, just do the steps like the screenshot : 

6.2. The skintone should now appear like this :

7. Go to Warehouse, click on "CAS Part", go to Data, you have to find "CompositionMethod" there. It should be set as 0. You have to change as 3 or else the skintone will looks grey in your game and you don't want that. Then save.

You are done! You can now test it in your game. If you aren't satisfied with how the overlay is looking, just try to change the color (make it more or less grey) or/and with the contrast. Enjoy.