Daddus1 - Take a look at the website of any of the major "mail order" hunting and fishing gear suppliers - Cabelas, Bass Pro, Gander Mtn., Sportsman Guide, etc. There are several of the fall restraint systems that you can buy. Priced from about $50 to about $150. All work well. "Seat of the Pants" and "Hunter Safety Systems" (HSS) are the two that I am most familiar with. I use an HSS vest type. All will have written instructions. Some come with a "how to use" DVD.
And now every maker of tree stands .... ladder, climber or hang-on ... of which I am aware (Summit, Gorilla, Strong Built, API, Lone Wolf, etc.) includes a fall restraint wit their gear. Some are better than others. Some are a "puzzle" as to how to properly put them on. And many are made for Mr. Average. Little guys and big guys are mopre or less out of luck with one of these generic sized harnesses.
One thing I strongly suggest that you do not do is use a "waist" or "chest" type "safety" harness. I am not even sure you can buy these any longer. The problem is that if you were to fall, these supoort your entire body weight by holding on to you above your waist and this can restrict the diaphram's ability to expand ... and you'll suffocate in only a hand full of minutes unless you can relieve the pressure "quickly".