User blog comment:TechBreloom/Monobook Editing/@comment-4674838-20120921232642

Hi, the Monobook skin is something you can enable for yourself in your Special:Preferences. It is not possible to make Monobook the default skin for all viewers of an entire wiki, however.

If you want to stylize the skin itself, you'll need to learn the Cascading Style Sheets language to write code for that.