A few of my pointers. When using jack stands or other type of support of lifting device on anything other than a hard surface (concrete or asphalt, on a cool day), put some type of flat barrier under the tool or it can sink into the ground or fall (I have a fiberglass plate that is use with simi trucks for this reason). While using a bumper jack, always chock a wheel correctly. I keep a rubber chock at my garage door for easy asses (a wood chock can slide). When using a floor jack, make sure it rolls as you are jacking (had a lawn tracker fall once when the wheels were struck in a crack and the jack plate fell off the frame). Take your time and plan before you lift anything that you crawl under. It only takes one mistake to give someone a bad or last day.