From the author's README on Thunderstore

A ReSkate Studio native patch for skate. containing Vans baggy jeans content.

Requirements

skate. with a game build supported by ReSkate Studio.
ReSkate Studio, for applying native patches.

Installation

Install through Thunderstore if your ReSkate setup supports this package format. Otherwise, import or apply the included native patch files with ReSkate Studio, following its current instructions. Do not copy these files into the game's installation folders manually unless ReSkate Studio's instructions specifically call for it.

Included files

The package includes the native patch marker and game asset files (initfs_win32, layout.toc, and Win32/).

Install PhatPantsGreen

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

Open ReSkateLauncher.exe and go to MODS.
Search for PhatPantsGreen 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.