This is a demonstration of how to install Knilling Perfection violin pegs.
www.knilling.com/
Perfection Pegs are internal planetary geared violin (and viola and cello) pegs, which give much finer tuning than you can generally manage with friction pages, and additionally don't slip or stick or wear against the peg holes. I've installed several sets, and have been very happy with the results. It really is a huge improvement over traditional friction pegs.
Knilling recommends professional installation. It IS a more involved process than just changing the strings, but if you're reasonably handy and careful, it's not too difficult to do yourself. And this will show you how.