You don't. iTunes Match only works on music (and music videos purchased from the iTunes Store).
@ Michael Allbritton, According to Tim Cook, movies have now been added to iCloud, but there wasn't any sort of explanation as to how this works. Don't just answer the question without researching first.
I don't have to do any "research." I suggest you do so first before castigating someone else. Start with this page <http://www.apple.com/itunes/itunes-match/>.
"iTunes in the Cloud" is different from "iTunes Match." You access the former by going to the iTunes Store and clicking Purchased under Quick Links on the right-hand side of the page.
iTunes Match is still only for music (and music videos purchased from the iTunes Store). It does not support any other purchased videos from the iTunes Store.