I'm not much of one for simple quotes of advice on writing craft. Part of the reason for that is it's not that simple.
It's about doing the work, the hard work, to get it done.
But, if you want quotes, if you want some of the things that ring in my head about doing the work, it's better for you to hear them.
The basics what they're all saying: Do the work. Keep doing it. It will not be easy. Put in the hours.
There's not a writer worth the ink their work is printed on who will tell you this is some easy lark. Anyone who does is selling something. There are tools to help improve, there is mastery of the craft, but all that comes from just planting yourself in front of your writing implement of choice and working at it.
I joke about "going down to the word mines", but it helps to keep that frame of mind that it's a process of work and effort, and it shouldn't be taken lightly.
And on that note, I've got plenty of that work still do to, so off I go...