I love grape juice. It is my favorite of all the fruit juices. I'm just not an orange juice person. And if you're willing to put in a little time and effort, you can have grape juice for free. Storebought juices are a) expensive and b) full of preservatives and mystery chemicals and flavor packets and really, who knows what else.
So to start out, you need grapes. My grandma graciously donated her concord grapes, because she has adequate supplies of grape juice to last her for another year.