Step 10: I Hate Waiting
Your epoxy should take about a day to set up, and two days to cure. Check the label of your epoxy, and go by that to be sure.
When it's fully cured, use a utility blade to cut/scrape off any excess epoxy drips from the bottom edges of your desk, and install it as you would any other surface.
And you're done!
Go show off your new desk to all your friends. Be sure to mention how much "cents" it makes to make a "change", etc. etc.