The first machining I did, with my little Sherline lathe and mill, I used a DTI and carefully indicated in the part for each cut. I got really good results, but it took forever to make anything. I started getting lazy and watching with a magnifier when the cutting bit would just touch the part. Then I got a Starret edge finder, now I wonder how I ever did without it! I still indicate some parts in with a DTI if want maximum accuracy, but 99% of the time the edge finder is quick and easy, with more than enough accuracy.
Enjoy your new tool!
Russ