Change with the Creation of a New Steam Account

Since the gender and race of the Rust character are determined by the SteamID, a new account automatically assigns other parameters to your character. That is, the way one would lose all the achievements and progress, not to mention in-game settings.

Modifications Using Server Settings

As a server administrator, you can use special server plugins or mods, such as Oxide, to affect the appearance of your character. This will allow you to customize the look of the characters on your server by using modifications or other clothing items added with plugins.

Third-Party Modifications and Custom Models

The players can change the texture or model of the game characters with third-party mods or settings, but that requires special tools and knowledge of programming. Still, such modifications will work for single-player and local servers only; moreover, such things may not be available on official servers.

Cosmetic Items

You also have the ability to change the look of your character using different cosmetic items that could be bought through the in-game store or could be obtained within various events and gifts. Hats, masks, costumes, and other stuff that allow you to personalize the look of your character; this does not change the core attributes, though. All of these methods have their own limits and are suited for different play styles, but one should remember that on official Rust servers, players cannot manually change the race or gender of their character; it's generated automatically, based on your SteamID.