You want to have a look at the front of MBUK for some pointers:
massively exagerate your riding position,
gurn like a twonk,
make sure everyone observing you has their head at 45 degrees so you look more ‘EXTREME’.
When discussing your extreme awesomeness in the carpark do it really loud so others can hear you (careful parking in prime locations, or next to other groups of cars as you arrive will make this much easier later on.)
Another one would be don’t actually bother riding (why would you? its clearly not what you’re there for – also you might scratch you bike, or get it dirty). Get to the trail centre, do the usual 60 minutes of visibly adjusting your bike and spraying it with half a dozen special product you buy, so it’s ‘just totally rad’, then ride out on the trail, cut through to the exit, wait a bit, and then sprint out of the exit, skid to a halt by your car and then pant a lot, fiddle with your phone (stopping the strava you weren’t running), and then nod with self satisified show of ‘besting your time’, a small fist pump can be added for good effect here.