(...Ignore the painful typo in the title lol) Full disclaimer: this might not be for every type of player or DM, but it's worked out well for me and my groups.

At the beginning of each session, right before or after the summary of last game, I ask each player a quick question about their character. Some questions are lighthearted, some delve into their personal backstory, and some are simply ways for me to find out how to DM them better.

Each question should take less than a minute per player. It takes up just a little time and can be done while people are getting settled, grabbing food, etc. It helps players who already have solid character concepts flesh things out more or just have a funny question to answer. It really helps players who have few backstory or personality details fleshed out. It also helps me as a DM learn details that might be difficult to learn organically and helps me sometimes foreshadow upcoming events through hypotheticals.

They're bite-sized and make it easier for some of my players to develop their character. Through these questions, one PC went from kinda a generic Paladin to having a personal side quest about his Paladin sister (upcoming), and a large side quest from his God that will spiral into involving his parents, his hometown, and all the other PCs.

Here is a list of many of the questions I ask: at the beginning of a campaign my questions might be more generic, but they end up more tailored as I think of more things I (and the group) would like to know about a PC. You can also just ask how they felt about a major event that happened last session.

Some of my players' favorite questions:

• For what would you sell your soul? (if the player doesn't know or can't think of anything, ask them why: are they content with their life, or are they just unwilling to rely on a higher power? Each answer is information)
• fmk (three other PCs or major NPCs)
• If you were forced to rob a bank with another PC, who would you pick?
• If you suddenly received 1 million GP, what would you do with it?

Feel free to comment with more question ideas or if you do something like this in your own game(s)!