From the author's README on Thunderstore

KK. Crew Jersey 2027 - VERSION JOUABLE

Version verrouillee : tu joues avec, c'est tout.

Installation :

Ouvre ReSkate et insère le fichier .zip dans instal .zip.
Ajoute "KK. Jersey.fbmod" dans la liste des mods.
Coche-le et lance le jeu.

Le flocage du dos n'est pas modifiable dans cette version. Pour le changer -> utilise le zip "MODIFIABLE"(disponible sur le insta officiel du @kkcrou) .

Install KK Crew jersey

You need ReSkate and your own copy of skate. on Steam.

Open ReSkateLauncher.exe and go to MODS.
Search for KK Crew jersey and click install. The launcher also installs anything it depends on.
Press PLAY. In game, the MODS tab of the ReSkate menu (Insert) turns it on and off.

Or install it by hand: download the .zip and drop it on the launcher window, or unzip it into its own folder in Mods\ beside Skate.exe.

Maps show up in the ReSkate menu's level list. To join a server running a custom map, you need the same map installed. If the game won't load after installing, see known issues.

skatemods doesn't host or review this mod. The download comes straight from Thunderstore. Only install mods you trust, because scripts can run code.