The best way to learn to write is to study the work of the men and women who are doing the kind of writing you want to do.
Telling a writer to relax is like telling a man to relax while being prodded for a possible hernia.
Writing is learned by imitation. If anyone asked me how I learned to write, I'd say I learned by reading the men and women who were doing the kind of writing I wanted to do and trying to figure out how they did it.