Propagating succulents?

Ok so I love succulents and Im trying to.propagate them to get my collection larger. If I knock leaves off or when I go to lowes ill buy some succulents but ill also collect the broken leaves and stems to bring home and try to root. Ill let them calous over and when I see.roots ill lay them in soil mist them very little every few days. But I think im doing something wrong because a lot of the leaves or stems wont produce roots.. Is there something im doing wrong?? And is there a better way??