There are a couple different ways to go about adjusting them once you find the correct length pushrods and ensure your sweep across the valve stem is good (checking rocker geometry) as mentioned by moper and RRR--strongly recommend you borrow/beg/buy an adjustable and ensure you buy the right length pushrods.
Here's one I found from Comp's instructions...keep in mind they're written for chevies, but the process can be used similarly
Turn the engine in the normal direction of rotation. Start with cylinder number one (1). When the
exhaust valve begins to move, adjust the intake valve to the correct preload. To reach zero, take the
pushrod between your finger tips and move it up and down while you tighten the rocker arm. Once
you feel the pushrod has no more vertical slack, you are at zero preload. Make sure the pushrod is
in the lifter and the rocker arm seat when making valve adjustments. As stated before the best
setting is .030” to .040”, or ½ to ¾ a turn of the wrench past zero. Now, you can move on to the
exhaust valve on the same cylinder. Begin by rotating the engine over again until the intake valve
reaches maximum lift and is almost all the way back down. Then set the exhaust valve using the
same method as the intake (.030” to .040”, or ½ to ¾ a turn of the wrench past zero). Continue
adjusting the valves on each cylinder in this manner until all valves are adjusted."
The above method in post #10 works well, but I never did well that way...I always did better one cylinder to the next...also, the amount of preload you put into it will change the way it runs. Too light, and it'll be a little noisy, and it'll essentially lose some duration/lift...too much and you can actually push the valve off the seat on the base circle...no bueno.
