Minecraft Bedrock Add-on Beginner guide

Many people wrongly assume that skin packs are only available for creation to Marketplace Partners. No! It's a very easy process, which can easily be fully automated by python. But that's not it: let's learn the syntax as usual:

The folder for creating skin packs is com.mojang/skin_packs/SkinpackName. For some unknown reason, com.mojang/development_skin_packs doesn't seem to function correctly, so you'll have to reload Minecraft every time between testing. You will not need a pack_icon, but you will need a manifest.json and a skins.json, as well as a .lang file in texts folder.

Note; on Android, the com.mojang folder is located in: Phone>games>com.mojang)

Skin pack Manifest

"format_version" can be 1 in this scenario, as v2 didn't change much for skin packs.
"name" is self explanatory. however, it isn't of gret importance.
"uuid" and "version" are already familiar to us. Both UUIDs in the manifest need to be different. You can generate them via a generator linked in Links and Contact. As a reminder, you CANNOT use the same UUID TWICE.
"type" in "modules" needs to be set to "skin_pack", of course.

skins.json

is used to define ever single of the skin texture files. Most of the options are, however, hard-coded./unchangeable. The skin .png or other image files are located in the same folder as manifest.json and skins.json, which is skin_packs/TutorialSkinpack in this scenario. My example skin files are named Niika.png and Senn_skin.png ~~guess where I took the names from~~.

The "geometry" object must be the same as on the example code in every object. Mojang revoked the ability to add custom geometries via skin packs, because the feature was abused.
"skins" array is where the object for every skin of yours are in. The skins will be displayed in the same order in minecraft as they are defined here.

In this example, I defined two skins. it is possible to define any number.

"localization_name" is going to be used in the .lang file. Think of it as the skins identifier.
"texture" is the name of the image file, located int eh main skin pack folder.
"type" is only accessible to marketplace partners, so leave it as "free"

"serialize_name" is for marketplace.

"localization_name" is the packs identifier, to be called in .lang.

texts/en_US.lang

Finally, we'll define the names of the skin pack and every skin in the .lang file in skin_packs/Skinpackname/texts/en_US.lang. Of course "en_US" can be replaced with any language.

skinpack.TutorialSkinPack=guide.bedrock.dev Tutorial skin pack

skin.TutorialSkinPack.NIIKA=Niika

skin.TutorialSkinPack.SENN=SENN

The first line defines the pack's name itself. It's done in this format:

skinpack.pack localization_name=ActualCustomName

The other lines define the skins' names:

skin.skin localization_name=ActualSkinName

Done! Now, when you open Character Creator, you'll see your skins available to be chosen! These skins aren't affected by the "custom skins switching in multiplayer" v1.14 bug.

Exporting the pack is easy: simply zip everything in the SkinpackName folder and change the .zip extension to .mcpack.

Note: Skin packs can be instantly generated from a folder with skins with AJG.

What you learned:

Creating a custom Skin Pack and exporting it;
Defining skin and skinpack names in .lang