Better to have at least one person to help you. [I admit I didn't always follow this advice.] This can make things not only go faster but also save your hind end.
Don't climb up on trunks, etc., that are balanced so that when you cut off part, the remaining part teeter/totters up or down and takes you along, saw running. [See above about taking advice.]
Spend some good long time looking over each area/section you are about to attack. Then take some more time. [This advice I did follow after about one time, lived through that one and figured this out.]
Well-meaning and/or nosey onlookers, property owners, etc., who want to "help" you by standing around too near and pulling on stuff you've just cut that instant or whatever must be thanked but moved away. Preferably to another town. It's your leg at stake.
I don't do it anymore. Somehow made it thru those times I did and someone else can do it.
Good luck.