Manual Installation using the System's File Browser
The approach is recommended, especially if you update from an older version to a newer one, as all previous addon preferences will be kept.
Keep in Mind
As of MACHIN3tools version 1.8, there is an integrated updater, that allows you to do an update installation from inside Blender, without loosing and previous addon preferences.
with Blender closed, find your downloaded .zip file
extract it, you need the MACHIN3tools folder - the one without the version
it contains the __init\__.py
file
copy the MACHIN3tools folder to Blender's addons directory
Attention
If you have a pre-existing MACHIN3tools folder in the addons directory, remove it first, before pasting the new version!
Blender's Addons Directory
Linux: /home/name/.config/blender/3.6/scripts/addons
MacOS: /Users/name/Library/Application Support/Blender/3.6/scripts/addons
Windows: C:\Users\name\AppData\Roaming\Blender Foundation\Blender\3.6\scripts\addons
Depending on your Blender version, replace 3.6
accordingly.
start Blender, open the preferences, switch to the Addons tab and search for machin3
activate MACHIN3tools and unfold the addon preferences