I first cut a line in the bark for the rough shape to be taken off. Looked at it from the right angle, made some adjustments. Then I used the chainsaw to cut that rought shape off. The rest was a lot of setting a line. Cleaning out. Looking from a distance and continuing.
During the carving I tried to follow the lines in the wood. THat way when it starts to crack, hopefully, the carving lines will coincide with the cracks. And I made some hollows of spots where branches were attached, again taking note of the shapes in the bark and underlying wood to set the shape. Working with ever finer tools.
I am planning on taking way more out though. But first the tree needs to accept this work. I feel that also here, taking away living wood, one should spread it over a few seasons.