Are you looking to give it a glaze or just a nice pop?  Keep in mind the factory typically bakes the glaze on the ceramic.  To add this after factory is possible, but a big project.  The glazing process is a much different process that takes more equipment and time.  I would not recommend using a topical (such as wax ) as it could create a slippery situation and a maintenance issue for the consumer.  I would use a good tile and grout cleaner (an alkaline) to clean it, auto scrub it, extract.  Then I would go over it once more with a neutral cleaner, and extract.  Once dry, I use a product called Mister 2000 (smells like baby powder) which gives the floor a really nice finish.  However, if you are planning to glaze the surface, be prepared to etch/prep the tile, (wear a good mask), mask the entire work area, purchase the glaze (we use epoxy.com) and it is applied with an airgun.  The strokes must be artistically even.