There's a mantra that I try to use, especially when I get stuck writing, editing etc. —sight, sound, smell. It's that simple. Immerse yourself in the moment, in the world you are building. Sometimes it helps me to think about an aspect of the place rather than forcing the scene. If I'm stuck on what happens next —what actions the character takes — I think about objects in that space, what people are wearing and doing around the main event, what kind of noises there are and where they come from, that kind of thing. It puts you into the place and time, feet on the carpet, hearing the air conditioning whoosh from the vents, looking around with your character(s) and noticing the world around you.