First and foremost, the salt of choice for any chef is KOSHER SALT. The large grains allow for proper coverage without over salting. Salt is a big one for me, I want people to get comfortable with proper seasoning of items. Over the course of time and repeated experiences, ones pinch becomes very accurate.
The three finger pinch is what I would like everyone to utilize. To practice, repeat the three fingered pick up and place on a surface, compare each mound, they should all be very similar.
When salting, it is best to hold your hand about two feet above the object being salted. The movement of your hand should mimic the motions of ringing a bell, moving side to side as the salt falls like rain. What this does, it allows even surface area coverage with little effort.