Trifolding is exactly what it sounds like. You're going to fold the prefold the long way so that it's three layers thick. You don't use a Snappi or pins for this fold. You simply lay it in your wrap-style cover and put it on the baby. Easy peasy.
A drawback to this fold is that leaks on the cover are more likely to occur, especially in an EBF baby. But the obvious benefit to it is that you can quickly do this without any hassle and anyone can learn to do it in seconds. It's probably the easiest one to teach a cloth-hesitant Daddy or a Grandma that never used it before.
2. The Twist
The twist is done by laying the prefold flat and then twisting it in the center before pulling up and over your baby. This fold requires a Snappi or pins to hold it in place though I suppose if you're really skilled, you could just use a wrap-style cover over it as well and close it that way. It means that you could get more leaks more easily though. The Snappi (or pins) is more likely to hold everything in.
I really like this fold with our premium prefolds because it takes some of the bulk that I'd normally have to fold down in the back and uses it across the twist in the center. One drawback I've found with my little boy is that you need to arrange the twist just so with a boy or it looks a little uncomfortable for them.