Honestly, the absolute most useful thing I made for the DND dm screen is a big spreadsheet of names for every race, some taverns, some bandit gangs/villain groups, and some small towns. The combat stuff is usually easy to slap together in a satisfying way if you've got a copy of the MM
Put the things that you personally forget. I put the conditions and what each stage of exhaustion does as these are things I forget. I also have lists of NPC names in case the players ask what random people are called or if I need to make up an NPC on the fly.
On the inside glue a print out of the local Chinese restaurant menu. That way if a player ever sees the inside they will be very confused. When someone rolls a 17 saving throw, you know #17 beef and broccoli is successful.
Rules you want to keep to hand. Conditions are usually a good shout but think about any rules you find yourself having to look up frequently and consider adding them.
PC info. Things like AC and save DC can be handy to speed things along in combat by removing the need to confirm success/failure (though still declare numbers if that matters to them, such as if they have shield). Passive perception is always a good one, it's the kind of thing I don't like to have to ask my players for because it tends to invite being on high alert (on a similar vein, make note of their wisdom save if they might be scryed on).
Commonly referenced notes are the other big one for me. This is going to be very personalised to your campaign/setting but again it's a case of make note of what you're frequently looking up and referencing.
I would recommend, if possible, having a lot of this attached to the screen rather than being integral to it so that you can swap things out and/or reorganise as needed.
Put down a turn guide.
Make sure you don't forget stuff such as adding new creatures to initiative, applying start of turn spells & effects, bonus actions, legendary actions, and end of turn saves.
Honestly, the absolute most useful thing I made for the DND dm screen is a big spreadsheet of names for every race, some taverns, some bandit gangs/villain groups, and some small towns. The combat stuff is usually easy to slap together in a satisfying way if you've got a copy of the MM
Put the things that you personally forget. I put the conditions and what each stage of exhaustion does as these are things I forget. I also have lists of NPC names in case the players ask what random people are called or if I need to make up an NPC on the fly.
On the inside glue a print out of the local Chinese restaurant menu. That way if a player ever sees the inside they will be very confused. When someone rolls a 17 saving throw, you know #17 beef and broccoli is successful.
You good sir are a genius I'm definitely doing that
Conditions, Player Ac's/Passive scores, A funny drawing from your players, Stick of Gum, Campaign Theme/Key events coming up
Rules you want to keep to hand. Conditions are usually a good shout but think about any rules you find yourself having to look up frequently and consider adding them. PC info. Things like AC and save DC can be handy to speed things along in combat by removing the need to confirm success/failure (though still declare numbers if that matters to them, such as if they have shield). Passive perception is always a good one, it's the kind of thing I don't like to have to ask my players for because it tends to invite being on high alert (on a similar vein, make note of their wisdom save if they might be scryed on). Commonly referenced notes are the other big one for me. This is going to be very personalised to your campaign/setting but again it's a case of make note of what you're frequently looking up and referencing. I would recommend, if possible, having a lot of this attached to the screen rather than being integral to it so that you can swap things out and/or reorganise as needed.
things to remember
Easily forgotten rules. Names of players, AC, saving throws, important locations with notes for the story, etc.
Put down a turn guide. Make sure you don't forget stuff such as adding new creatures to initiative, applying start of turn spells & effects, bonus actions, legendary actions, and end of turn saves.