This should be verified by planet bluegrass staff but I believe the best way prior to anyone receiving physical tickets (wristbands) is to use the Seetickets interface.
From that portal users can send tickets to another person using an email address. Once the wristbands/passes are mailed (there was an option for will call and for mail), the physical bands/passes should be relatively easy to identify.
Regardless try to interact with trusted members of this forum as much as possible. Aside from that use common sense and if it smells like a scam, run away.
Most importantly, never EVER pay above face value for any ticket.
Edit - PB staff answered this question here:
https://www.festivarian.com/index.php?topic=39195.0
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