When I was employed, I was pretty much the most skilled in what I did where I did, so most of the customers and co workers were understanding that I wanted to do things my way. I did have one co worker who was a screw off and had a poor work ethic, so my choice was to tell him I wasn't going to work with him unless he did his share of the workload...we had a few major disagreements now and then but when he realized how dependent he was on my skills, it pretty much settled the issues.
If someone persists in being confrontional, I say my thoughts, listen to theirs, and we can usually reach a compromise.
I do not like to argue, so compromising is the art of settling differences, wish I was better at it.