I've owned my lift for 2 years come November and along the way I've found a few things worth sharing. Feel free to add your own tips here especially if they involve safety.
1) I took almost a year to realize that I wouldn't be upright under my car while working like you see in the advertisements. Oh sure, I do some work upright but for the most part it is very uncomfortable and results in a stiff neck. So, raised appx 2' I use my creeper as it is much more comfortable to work while laying than upright.
2) It was another year before I learned that the best benefit of having this lift was to raise the car appx 2ft off the ground so I don't need to bend over for hours at a time resulting in a back ache.
3) Clear the area below before lowering your lift. Twice!
4) Clear the area above before raising.
5) Jack Extensions - My MaxJax comes with 4" lift extensions to give you a little more headroom however these can't be fitted beneath the 914 because it sits so low. I need to lift it a few inch's with the lift then lower it upon blocks. Only then is there enough room to insert the extensions. I can't use wood blocks under the longs to hold it higher because I have fiberglass valance covers. So I placed blocks beneath the wheels instead. This doesn't work worth a Continental Damn because of the 914's suspension. As I lowered the car it would walk to the side if the fronts touched ground 1st of it would walk forward if I'd left the Ebrake on or left it in gear. A couple of times I thought the tire would slip off one of the blocks as it was lowered. I cured that yesterday. HF had the 12"x18" furniture dollies on sale for $7 so I now have 4 of those to place beneath the wheels when using the extensions. Cheaper than the purpose made dollies that sell for about $40 each and rated at 1000 lbs. Much safer now.
6) Don't leave your car on the lift unnecessarily especially if you live in Earth Quake regions.
7) Use the lift's safety catch's or safety lock outs.