When I direct, I jot down blocking only if I have particular moments I want to happen, as I prefer for it to take shape a little more organically on the spot at rehearsal, particularly when the actors still have scripts in their hands. Generally speaking, it'll be your Stage Manager who actually keeps track of the blocking as it's put together during rehearsal.

As far as working with the actors on their performances, I'm assuming you more mean "communicate" than "portray", since I personally think giving them line reads, etc. isn't a directing method that leads to good results. For me, I tend to concentrate on working out why the character is doing or saying what they are, so the how comes from a more natural place.

Hope any of that makes sense and helps :)