1- Create a package of a theme
To do this, go and see this tutorial
2- Installation of the theme
We take the example of purity2fr_t3_green
First, go in the administration of the template.
Under the tab "themes", we will use the fonction "upload package file"
Then find the package file on your computer.
When lhe file is uploaded, the theme is now visible in "local themes"
3- Activate the new theme.
To apply the new theme, go in "profiles"

and in "Advanced settings" and "theme settings"

Then click on the pen, and select "purity2fr_t3_green"

Apply and save the modifications.
Your theme is now active.
















