Rick Roll Em

Ask one of the patrons how their driving is

scream "HEY EVERYONE I HAVE AN IMPORTANT ANNOUNCEMENT" and then say hi

don't tell anyone I'm FireNationPhoenix and then reveal it at the end

Put legendaries in the gyms and make it obvious that it's you

name all my gym Pokemon my username

Blue Spirit Mask

Start a flash mob

Bring everyone at the fan meetups coffee and tell em its hot chocolate

other(suggestions)