One way to ensure spotlight time for the players around your table is to write it into the adventure. This encounter favors a cleric, this one a rogue, this one a fighter, et cetera, et cetera.
All well and good if the adventure is exploration, say of a dungeon, and as GM, you’ve devised encounters for certain areas.
But what happens when the players take the adventure in a different direction and the GM has to resort to improvisation? How do you endeavor to provide spotlight time then?
Tracking by quarter hour
This little trick I picked up by running convention games, which must end at a specific time.
Basically, you look at the time remaining, and think about achieving certain goals in 15-minute chunks. These AREN’T hard and fast time frames (OK gals, we’re at 14:58:07 and counting, who’s up next?) But rather, you make a mental note to spotlight a particular player in the next 15 minutes. After carrying through with it, you do it again for the next player.
If you need a visual cue, I suggest keeping a Trivial Pursuit token nearby. They are divided into six wedges (which works if your table has six or fewer players). Fill the wedges in as you successfully give a player at the table their spotlight time.
Remember PC motivation
When looking for spotlight opportunities, don’t define them solely by character class. If it’s a home game or ongoing campaign, then you should have a sense of the motivations the players have assigned to their PCs.
Actually, feeding a PC’s motivation may likely be as rewarding a spotlight opportunity as matching their class abilities to an encounter challenge. Here’s a chance for their PC to grow, indulge in a little wish fulfilment or sink their teeth into a little roleplay with an NPC crafted for them.