Thanks for the mention Gwenna Laithland.
Since you used the word “MUST”, I actually disagree with point 1, 2, and 4.
Some of my best stories were written when I had just woken up and didn’t take the time to get dressed.
While I mostly agree with picking a time (I usually write a 5am), two of my top five articles were written at random times when I was just very inspired and jumped right on it.
Last, I find setting goals actually reduces my creativity since I focus on them more than the writing “process”.
Getting over your fear of rejection is the single most important one in there I’d say. And this applies to anything in life. I’ve been rejected by about 100 literary agent for a book deal. I’m still standing and making money blogging. Some day I’ll get a book deal.