For calves with longer thinner type hair I like to back drag the neck with my andis and a pair of medium blades before i use the blocking blades to finish. Makes it much easier to see what you are doing when you got the longer "stragglers" off there first. Practice at home first. I will pass on some great knowledge a great family friend of ours ,who happens to be a retired pro fitter, gave me when I first started clipping, I was too afriad to touch a set of clippers and after hearing his advice I clip all of our own calves...here goes...
"Nothing to be afraid of, it is only hair....the best way to learn is to srew it up, not very comforting, but at least you will know how not to do it next time"
Not exactly what i wanted to hear at the time, but as I do more clipping for myself and others, I have grown to realize how very true that is!!!
GOOD LUCK <party>