Getting Started

Get a licence. Choose a plan on skin-creator.com, or start the free 14-day trial. After the purchase you get an e-mail to set up your Dashboard account.
Create a tenant in the Dashboard. A tenant is your organization: your licences, servers and team belong to it.
Activate your licence under Licences.
Create a server under Servers. Give it a name and select the licence. The Dashboard then shows the Server Secret.
Copy the Server Secret right away. It is shown only once. If you lose it, generate a new one on the server's page; the old one stops working immediately.
Install the plugin. Download the newest version, put the .jar into the plugins folder of your server and start the server once.
Configure the plugin. Enter Server_Id, Licence_Id and Server_Secret in plugins/SkinCreator/config.yml. The tab Plugin & setup on your server's page has a button to copy all three values. See Configuration.
Restart the server. The Dashboard shows Connected as soon as the plugin is connected.
Try it in game: /skincreator edit.

Optional next steps:

Choose the skin packs and the skin limit per player: Server Settings
Upload your own skin parts: Custom Skin Packs
Set a default skin for all players: Default Skin
Add your own MineSkin API key so saving skins is faster: Team and Account

Networks (BungeeCord, Velocity)

Install the plugin on every backend server, not on the proxy, and create a server in the Dashboard for each of them (steps 4 to 8). Each server uses one server slot of your plan. If SkinsRestorer is installed on the proxy, remove it there so it doesn't overwrite the skins when players switch servers.