This is how I do it.
First I paint a bullet with a sharpie marker.
I make a primer less, powder less round, I insert the painted bullet in a case without crimping so the bullet can be adjusted in the neck without a ton of effort, I make sure the bullet is sticking out of the case far enough.
I then load the "round" into the action and close it, takes a little more effort but it works for me, take it out and measure the COL, if the bullet sticks in the lands a little or comes out of the case, push it back out with a cleaning rod and use the score marks on the marker paint to determine the depth.
I then go back so the bullet is .005" off the lands and call this my starting point, load my recipe and shoot in multiple groups of 3, move the bullet back in increments of about .020" looking for changes in accuracy.
I never make any rounds with the bullet all the way up against the lands.
Once I see a change in accuracy I will continue to move the bullet depth in .020" increments and look for another change of accuracy, this will give me an idea of how wide the sweet spot is, it has been my experience that 1 or maybe 2 more moves will tell me.
Once I determine that I can go back to the middle of the sweet spot and start adjusting bullet depth by .005", or .002"
I don't know how standard my methods are but it has worked pretty well for me.