Well, here's my dilemma...lol...I hate to trick my mare into that...she is really old...around 28 and as sweet as can be....so, I want it to be my gelding (wow, that sounds mean!), but I don't want to risk putting him in there, find out it isn't working and watch him go over the fence again. Sigh. What a pain in the a$$.
If you're too chicken to touch it, you can buy a fence tester for about $10. One way to touch-test is to wear rubber boots and hold the wire firmly, rather than just touch it. It's not the pain that gets you (or the horse) it is the shock/surprise factor.
My friend introduced a few horses to electric due to their history. What she did was put them in the enclosure, called the horse to the fence line, let the horse relax and then she moved the wire with a long stick. The horses see the fence move, not realizing it's from her. She usually makes a point of ensuring the fence touches them. One time is enough.
I had a stud once who thought he was stronger than the electric fence. He reared/twisted near the fence and somehow or other managed to get his important parts on the fence. I'm still not sure how he did it without going over the fence, but he NEVER went any NEAR the fence again! :)
I also had a horse that jumped the fence once. I put it up higher and she never tried again.
I just put everyone in....one by one they touched it. Never agian did they touch it lol My fence is set super high because we have a cow, he gave it a good lick,and boy did he jump! I also forget to turn it on. I really only turn it on when I see someone testing it. Its a pain in the but too turn on and off 10 times a day lol