Jericho (Arabic أريحا Arīḥā Hebrew יריחו Yəriḥo) is a city in the West Bank.
If travelling from Israel it means you'll be crossing into Palestinian Authority area. For instance, if coming via Highway 1 (Jerusalem - Dead Sea), hitch a ride on that busy highway and get dropped off at Almog junction, at which point you'll have to hitch the few kilometres into Jericho. With Jericho being Palestinian Authority territory, it'll only be Palestinians on their way to Jericho driving this section. It's best to walk a hundred yards or so in the direction of Jericho and hitch - away from the service station. No need for a sign as it's obvious where you're going. Drivers will do their best to drop you off at a convenient point.
If you're on Highway 90 (Jordan valley), get off at Allenby Bridge junction. From there you'll catch the traffic going from Jericho to Jordan so you shouldn't have to wait very long. Bear in mind that this particular junction is quite desolate, with no service stations nearby, so it might not be a good idea in the middle of summer. - jamesor2.
West towards Jerusalem, East towards Dead Sea
From the main square (where taxis and shared taxis stand), walk southwest out of the city. Though you'll have to avoid taxis, it's easy to stop a car from anywhere on the road. Ask the driver to take you at least several kilometres to the intersection with Road 1, where you can then hitchhike in west towards Jerusalem or east towards the Dead Sea from the bus stop/trempiyada.