Edit until you get it right.
Make sure there’s nothing to change
With all good, it won’t be strange
To let agents and publishers have first sight
Of your magnum opus, your so-cherished work
Send it off too soon, you could feel like a berk.
The above sums up most writing advice in one verse!
The writing life can be such fun
Proving to yourself it can be done
By you as you invent new tales
New worlds, showing when your hero fails
And succeeds in making villains run.
And this one reminds authors of what I think of as the first rule - enjoy writing!