I was helping a family member at their house cutting some zip ties off a slide and slipped I cut major artery and tendons. What can I do?

OK, I'm really sorry about this incident. I hope you get better. So there is no automatic liability if you were injured on another person's property. The injured party has to prove that their damages were caused by the negligence of the property owner or property manager, it does not appear from your fact pattern that they did anything negligent to cause your damages. If they do have a homeowners insurance policy, usually there's always a med pay portion that they will tender provided that a person was injured on the property and you suffered damages. However, that being said, you should still search for an attorney in Colorado as there could be liability based on some kind of clever argument that they gave you a tool that they knew or should've known was defective and you had no knowledge that this tool was defective. There could be other arguments you could make, but that's just one off the top of my head.