I posted an explanation on how I went about tuning my bow myself after many many disappointments at local bow shops. I do mean bow shops in the plurality sense.

So it got me thinking, what do I want? I want my arrow to shoot off that bow dead center from the string. How do I go about ensuring I have it dead center? Well my vernier caliper (available at any hardware store for about $15) is digital down to the 1/100th of a millimeter. So after some rigging using 2 clamps, 2 carpenter levels, 1 bow square, a pair of nock pliers and my caliper, I can say my arrow is coming off my bow dead center down to .01 mm.

First I verified my rest was centered by making sure from the straight edge on each side to the arrow was exactly the same. Then I took my bow square and instead of using it to set my nocks directly, I attached it above on the string where each point was just strings in order to ensure it was attached the same at each point. I used my caliper again to ensure my arrow was running completely perpendicular to the bow square. Again, confirmed to .01 mm

Here are some pictures. For those who want to just double check the job your bow shop did, just using a single level and the caliper will provide you the evidence on whether your rest is centered.