Know this from the start, the Hi-Lift Jack is an inherently unstable tool. Get familiar with the main parts and what it feels like to both lift and lower a load. Keep your head and any body parts from getting in between the arc of travel of the Handle and Standard.
When jacking up, the pressure will be on the downward stroke of the handle. When lowering, the pressure is on the upstroke. If you're not prepared for it, the handle can swing up with enough force to crack a skull open. It is possible for the handle to automatically kick back down, and the vehicle will drop rather quickly, and the Hi-Lift can get kicked out. Be careful! This is a tool that requires training and a good sense of familiarity before pulling it out on the trail when you're really stuck.
When you're lifting a vehicle, it and the Running Gear do not travel in a straight line. There is a slight arc, that leans in towards the body panels. Think of the difference lifting on a 2 or 4 post lift at a shop vs. lifting by a slider on one side. You can account for this by leaning the Standard slightly away from the body when getting it into position. Other options to help mitigate the Hi-Lift from crunching a body panel is to fold in the side view mirror and align the Standard against it.
You can also use a pool noodle, slit down its length, to wrap over the edge of the Standard. This may not prevent a dent from happening, but it can help prevent a sharp pinch of the metal or chipped paint.
