I was nervous my first couple times doing it. I'd just watch a couple videos if you can't have someone show you in person. That's how I learned, that and practice. I wouldnt do it more than a couple times to one snake in a day though. When you do it place you thumb in front of the vent pressing down firmly but not hard and I like to bend the tail down a little then starting about an inch below the vent roll your thumb of the other hand from the right side of your nail to the left side, again firmly pressing down but not really hard.