grab an uneven clump of hair towards the front of the hairline and kind of off-center (an amount that would be used for bangs (or "the fringe")). put this behind one ear and pin with bobby pin (if you have one) just behind ear. if you have a barrette do it just over your temple.
don't do it tightly, loosen it, so it adds volume.
part the rest down the center all the way to the back of the neck.
then:
2 ways to do pigtails:
("girl next door" look)
grab left part just under the ear, wrap a tie or band around it. do same to right part. then pull either band down to the jawline so they are symmetrical.
or
(fun/"cheerleader" look)
grab left part just behind the ear, and pull up and tighten until pigtail is positioned at eye level. wrap tightly with hairband. do same to right side. this one'll take a few tries to get it symmetrical.
it's a lot easier if you use a headband to gauge the position.