Turn the engine till number 1 cylinder is at top dead center. Remove the valve cover. There are slots cut into the back side of the camshafts that a special tool slides in. You can use a flat bar as long as it fits tight and the cams do not rotate. Putting number one cylinder at the top will line the crankshaft up for you. Making sure the key points up and the piston is all the way up will help you line it up.
If this helps you out please accept the answer. If you need any more help just ask.