set the number 1 piston to Top Dead Center (TDC) on it's compression stroke. To do this, I used a 19mm socket on my breaker bar and rotated the crank bolt clockwise until the notch on the crank pulley lined up with the "0" mark on the oil pump cover.

When the number 1 piston is at TDC and on the compression stroke, both of the intake and exhaust rocker arms should be loose (in the picture I am actually able to slide rocker arms off the cam lobe - this is loose).

If they are not both loose, you must rotate the crankshaft bolt 360 degrees since you are not on the compression stroke.

JeffsToyo:
TDC of the firing stroke..The piston is at TDC twice with the #1 spark plug removed, put your finger over the hole as you turn the motor over and when you feel the air being pushed out you are at TDC on the firing stroke. You could remove the valve cover also and check for clearance with the #1 rocker arms to see.
Good luck
Jeff S.

42D22R:
Alternatively, if you ain't got someone to help you, stuff a small piece of paper towel in the #1 spark plug hole, turn the motor over just a little at a time until the paper towel pops out, then line up the timing mark on the crank with the 0* mark. She should fire right up if you stab the distro in on #1, then throw the timing light on

Good luck