This installation tutorial is only for old Minecraft versions ranging from 1.12.2 - 1.7.2, which came with a Wurst installer. Newer versions work differently. If you want to install Wurst for Minecraft 1.14.2 or newer versions, please follow the Wurst 7 installation guide instead. If you want to install ForgeWurst, please follow the ForgeWurst installation guide instead.
Download the Wurst Client, if you haven't already. Make sure to get the latest version that is compatible with your Minecraft version.
Extract the Wurst installer (.ZIP file) that you just downloaded.
Find "Wurst Installer.cmd" among the files you just extracted and run it.
Click the Install button.
You will normally get a message telling you that Wurst has been successfully installed.
Open the Minecraft launcher. (Close and re-open the launcher if it was already open.)
If you want to use MultiMC instead of the official launcher, follow this guide from here.
Select the new Wurst profile and press PLAY.
Download the Wurst Client, if you haven't already. Make sure to get the latest version that is compatible with your Minecraft version.
Right-click the Wurst installer (.JAR file), select "Open with" and then choose Java.
Click the Install button.
You will normally get a message telling you that Wurst has been successfully installed.
Open the Minecraft launcher. (Close and re-open the launcher if it was already open.)
If you want to use MultiMC instead of the official launcher, follow this guide from here.
Select the new Wurst profile and press PLAY.