The first rule of putter selection is how they feel in your hand. Putters will have different edges on them; fat or thin, beaded or non-beaded. You want a putter that feels good and that you can throw the same way each time. Beads and slight changes of the disc are useful to keep the same finger and grip placement each time. Once you find a putter you like, get several more with the exact same weight. This is key for practice and consistency from shot to shot. The best way to practice is with a stack of 5 putters that are all the same. The best way to warm up before a round is with 2-3 putters.