Just impressioned my first locks, starting simple with a Master No. 5 & No. 7. An obvious thing I learned along the way: look for marks whose size is the right order of magnitude! I was chasing marks that were way too small or large for the size/bevel of the pin tips, and patiently waiting for a clear mark helped me calibrate the right mark sizes to pay attention to.
Also, re-read everyone's guides a billion times!


