...on shot selection.
The camera is the viewer's subconscious. In The Seventh Seal, in scenes when Max Von Sydow is playing chess with death, we may not realize it but each shot (and chess move) feels like death itself - lonely and calculated. Orson Welles cut out the floors in Citizen Kane to shoot from below - this famously showed the ceilings, but it also made Kane feel larger than life as you looked up at him. Another Welles film, Lady from Shanghai, uses mirrors to make the audience feel as confused as the main character. In Dr. Strangelove, Kubrick uses a handheld camera outside to show the chaos brewing while everything indoors feels chillingly calm. In Kill Bill Part 2, you feel the claustrophobia after the Bride is buried alive by his use of black.
The images the camera captures tell a story consciously, but the camera has a way of adding the extra details that you don't explicitly state. You let the viewer discover those themselves with little hints to the subconscious.
A shot list helps keep notes of both the visuals you want to convey outright and also the subconscious voicing you want the camera to speak. Creating the shot list is one of my favorite things to do in the pre-production phase. I like to be prepared and believe that planning for months in advance is better than trying to do it all in the short amount of time you're spending on the shoot.
Here's an example of my shot list from day 3 of shooting Kitsune:
My shot lists tell me what I need to know to feel confident I've shot what I wanted. I shoot to the cut, and allow a little room for extra coverage in case the edit needs it. I include notes for my directions and also choose which lens I'm going to use. I make similar notes in my shooting script. I try to reduce as many decisions as possible on the actual shoot day. On shoot day, if I'm making a change, I'm not doing it under pressure and I'm reading the actors and environments to best tell the story.
This isn't always possible though. Documentaries require you to constantly watch the air in the room to decide where to go next. I tend to shoot documentaries where the camera is an active observer in the room. What would they be looking at? What is fundamental to the core story? In narratives, some scenes require you to reblock them because you discover some issue (the doors on the wrong side of the room, for example.) And sometimes, you see something and get a spark. I think having these lists offer you a safety net to free up your mind to notice those sparks, though.
When picking shots, I think about what you need to see to understand the story. The camera is a character in this play and has a certain voice. Just like a character, it needs to feel consistent, and this natural feel creates the "style" of the film rather than falling in love too much with a certain shot you think looks interesting. It moves in a certain way and focuses on certain points. You may want the audience to feel closer to one character over another, and to do that the camera needs to be closer. (A lot of people frame their shots in post, but I don't like to do that. The lens has a natural way to distort and compose that in a way we feel.) Shots should have a beat to them, like music. I like to let some shots linger a bit, similar to a diminished note. It feels slightly uncomfortable as you wait for the next beat to hit. I tend to like locked off shots, but I also like the sense of discovery a gimbal shot has. I don't like using "creative cuts" like swish pans unless they're meaningful to the relation of one scene to another. I think we overuse these now because we confuse "flash" with "substance." Someone might compliment you on the use of it, but its much more important that they feel connected to the overall piece. At least in my opinion.
David Mamet wrote a book called "On Directing Film." The book is a great lesson in planning shots. It tells how to break down the scene into its necessary elements and tell the story in as few shots as possible. It's a great tool in learning how to efficiently tell a story.