We learned to do this when I was in high school back in Canada. Making your own jig is quite simple, but cutting the cove is a little time consuming. You don't cut it all in one pass, or the cove doesn't end up smooth. You can either start in the middle of your desired cove, run it through the saw so your cove is around 1" wide, then increase the angle that you present the piece to the blade and then widen the cove. 3-4 passes is usually enough, depending on the size of your cove.
When I took a cabinetry nightschool course many years later, the approved method was to keep the angle the same for each pass, but raise the blade for each new pass. That's the way I prefer to do them now if I do use my table saw - it's a bit quicker, and for each pass all your changing is the height of the blade so there's less chance of making a mistake.
I will say that I'd not try this on anything smaller then a good, strong cabinet saw. I'd do it on my 3hp delta unisaw, and in the school shop we had 3 or 5hp SawStop's or Powermatics.
If I had the time though, I'd use my wooden molding planes. I've got most of a set of hollows and rounds now, and it's just fun to use them. To finish a larger cove, I'll often cut a card scraper to match its curve. Give it a few passes with the card scraper afterwards and everything ends up nice and smooth.
All that having been said, I should point out that Peter Sefton is a professional and teaches as well - so my advice is to listen to his advice.
