How to start Cross Country?

I really want to try cross country but I don't know where to start. Any suggestions?

First step is finding an eventing trainer. Or at the very least an eventing clinic that has a spot for novice/greenies.

Do not try it alone with no coach. It is not only dangerous to the horse, it is dangerous to you. You can very easily kill both of yourselves trying cross country without a coach. It is completely different then jumping in an arena.