If you're going to make them portable-
You can build walls- 4X8 out of 2X4 or 2X2. Use the orange perf stuff for the wall part. You can stand them up,as walls/vision barriers, or lay them down as low walls/obstacles. Use 1X2's screwed to these to make ports you have to shoot over/under/through. You can make doorways/halls, etc., by screwing these together. You'll also need to make some braces to hold them up, basicly triangles- screw to the walls, nail into the ground. For which you'll need to drill holes in the walls and pick up some big surveyor's spikes to secure them into the ground. Big rocks/sandbags/old tires work too.
Targets- you can buy IPSC targets and tape online, use USPSA scoring or make up your own.
All that's left is imagination and help setting up.
Rules- start with USPSA and modify as/if you need. Safety- it's the same everywhere- when your course of fire is set up make sure that any possible ange of fire is safe, make sure you're not setting the shooter up for an unsafe muzzle direction, etc.