Some time ago I shaved my brother. It was not the most confortable of experiences for any of us, but I did manage to give him a close nick-free and irritation-free shave. I was very proud. But it was a thing to to once and only once. The lack of a propper chair was an issue, though...
And yes, I've left that to professional barbers ever since.
It was something I needed to do, though and my brother was willing enough and interested enough to trust me with a sharp blade arround his face and neck...