In my opinion one of the most important things to remember as a DM is game Flow. One thing that I do is assume some of the smaller actions that my players would take for example: if a player says I want to head to the store to buy something when they get to the store I'm going to assume that they want to walk in and then narrate them entering the store, what it looks like, who runs it, Etc.... One mistake that you can make is too have them walk to the shop, and then stop in front of the door, and then have them tell you they're going to open the door, and then have them tell you that they're going to walk into the door, and then have them ask you what the surroundings look like. That is far too many stops and too many questions that the players have to ask as you. A DM you should be explaining the world and its surroundings and and let the players express to you when they want to have control or give more weight to a seemingly small action.
The next thing that I think is very important is to put your characters in more of a realistic situation that helps the game Flow a lot for example : let's suppose that the group has to make a fairly quick decision but they sit around just talking about it and talking about it, one thing that I like to do is make the NPC's or the environment interact with them in some way to help Quicken their decision making, like maybe they're speaking with a wizard who wants to have an answer right now to the question he's asking and so he decides to just kick them out and not use their help potentially, because they were taking way too long. You can make that situation work with minor or major characters if it's a major character that involves your plot or your story hook then maybe after the character kicks them out he comes to his senses or he's put into a position where he decides he really needs their help and he goes back and he's less Hasty but it is good to try to keep things moving and have your characters always trying to accomplish something even if it's not part of some Grand story Arc. Small interactions are very important for making your game feel the way you wanted to, and flow the way you want to.
If you would like more posts like this comment down below and let me know what you think and what you would like my future posts to be about.