OK this picture should make things clearer!
the snare is attached Via the tether to whatever is holding it in place
note the pegs to guide the rabbit into the snare and the triangle shape of the wire where the tether is attached which helps the snare to stay in place
this is one of Eds snares that we set up whilst out last weekend
remember that you must have the permsion of the land owner (as we did)
and i recommend that you find somone who has experiance of laying snares (like your local game keeper) to show you how to do it on your first trip