Well you got to figure out what sort of hook you want to put in.
In my old games (Cpunk 2020, and Shadowrun) I liked to use
-Technology. Corp A has developed something Corp B wants.
-Culture Shock. Gang Wars, Mob Issues.. fall out from old wars ('Borgs vs Moreaus)
-Alien Invasion: That was fun.. the players were caught in an alien invasion.. the aliens didn't realize how much Humnaity would advance in 2 centuries.. they jumped in, shelled earth with bombs that worked on the nitrogen in the air.. huge explosions around some areas..then the AIs running the mass drivers on the moon hit them with a few megatons of lunar junk.. insert massive ground war with neither side making a lot of progress and a lot of side journeys.
Lots of stuff. Read William Gibson's Nightside series.. Snow Crash.. they always inspire me.