An advanced technique: ask your players to make shit up.
Like, the players decided to go to the wizard university the wizard PC graduated from. So I ask him, "what's their entrance hall like?" and let him just riff on it for a while. Players feel more engaged with the world, and it's a little less work for me.
Warlock is trying to commune with his patron. I ask, "what is your patron usually like?" and the player is delighted to describe "the great sculpin" in detail. This then inspires me further.
Note that some players are very much "just tell me a story" and don't want any input, and won't like this. Some players are also shy and don't think well on their feet. And some players are just really bad at staying on theme. But if you know your players , this can be a powerful technique.