Download the Fabric installer.
Right-click the Fabric installer, select "Open with" and then choose Java.
In the Fabric installer, select the Minecraft version you want to use and press "Install".
Go to the Fabric API page and select your Minecraft version at the top right.
Then download the latest (top-most) version of the Fabric API for that Minecraft version.
Place the Fabric API in your
%appdata%/.minecraftinto the address bar.
Download the Wurst Client, if you haven't already.
Add Wurst to your
If you have followed my recommendations above, you will already have a "fabric-loader-..." profile in your Minecraft launcher.
Make sure that the "Modded" checkbox is enabled, otherwise you can't see your Fabric profile!
If you don't have the Fabric profile, go to "Installations" > "New..." and copy these settings.
Then select your Wurst/Fabric profile and press "Play".
Be sure to click away any "player safety" nonsense. These warnings have nothing to do with safety!