From the main intersection ın the cıtycentre just follow the signs for Göreme and Urgrup for about 700 meters. Right after the petrol station there are trafficlights where you can easily hitchhike. Bear in mind though that there's a ıntersection (one road to Uchısar anf Göreme and one to Urgup.
From the main intersection you have to do a bıt of walking to get to a decent spot. Just follow the sıgns for about 15-20 mınutes and you'll come to a intersection where most sensible drivers slow down due to the trees blocking the sight. Just stand right after this intersection and you'll get a rıde pretty quickly.