The original post is titled The Top Ten Things They Never Taught Me In Design School, but the ten rules of thumb are (IMHO) applicable to any professional.
Rule #2 I would amend to "95 percent of any creative profession is mundane work", as much of what you will do as a creative professional (whether credentialed or not) will be ordinary and everyday rather than revolutionary. If you keep your eye on the end goal, you will come to appreciate the mundane aspects of your profession (at least, it works for me) (this is also mentioned at the end of the rule).
