Any tips on doing this?
Sit down and figure three things for yourself:
- What things of the game are important to you and want to stick to your players. Make a short list of like five things, put them in order of priority. Write that down, that's the game you're running as DM and that's what the players remember of this games afterwards.
- What is important to you for this session, what do you want to stick for your players? Pick one to three points at most, do not order them.
- Write down for each encounter what's important for you and what the encounter is about in terms of the game you run - in general with you as DM, but also in specific to your story. Write down ONE thing at most. What is this encounter about? In encounters where it's not important to play by RAW and 100% played out, well, that's the one you can skim on, cheat on, drop parts out.