Shoot it for a few shots. Maybe, 20, just blank bail it with the tube off if you have one on. Next determine which way the string is twisted. Lightly press the bow and remove one strand from one side of the peep and place it on the other side of the peep. Then take a strand from that side and place in on the other side. Do this in either a clockwise motion or a counter clockwise motion, until you have the peep properly orientated at rest.
Now, do some more blank bailing and observe if the peep is rotating. If it is rotating, move one strand from one side of the peep to the other. This is sort of a guessing game, If the peep sight rotation decreases or increases when you draw the bow, then you will know which is the stronger side of the string. However, it shouldn't take over one or two string to stop peep sight rotation.