I put a running trail through my property. I have little kids so it can be tricky getting runs in since I can't leave them along yet. Having a running trail lets me run and have them at home.
I walked through the property and figured out where I wanted the trail. Then used a chain saw to take down any trees that were in the way. I didn't want to cut down anything big which is why I planned the trail ahead of time. I cleared the path area of any stumps, rocks, dead limbs ect and then took a Kubota with a back blade and scraped a 3' path.
I run on it and my dog uses it as well which keeps it pretty clear on its own. I periodically drive my lawn tractor through it and mow it down as the plants try and encroach on it.
Its basically the same process that mountain bikers use for keeping the trails they use clear. If you use it, it pretty much keeps care of itself.
Some people have said use mulch or wood chips. I strongly recommend against that. I have run on paths with wood chips or mulch. It constantly is getting kicked up and getting into your shoes and socks. Plus its expensive and you have to keep replenishing it. If you want yourself a fancy mans running path do something like crushed gravel (don't use pea stone). It will be expensive though and in my opinion isn't worth it.