It really depends what your attaching onto, Dystopia used to have little D locks (i think they may have a different name) though theres no reason not to use a carabineer.

Dystopia attaches its bungees on one side to some loops of rod (to which its knoted on), and on the other it froms a loop in the bungee as i double it back, this then attaches onto two bolts and the tension stops the bungee coming off.