Here is some prose Ernest Hemingway scribbled on the envelope of a letter he wrote to F. Scott Fitzgerald:

What about The Sun also and the movies? Any chance? I dint put in about the good parts. You know how good they are. You’re write about the book of stories. I wanted to hold it for more. That last one I had in Cosmopolitan would have made it.

(The letter itself is wonderful, and you can read it here.)

I dint put in?  You’re write?  Of course, Fitzgerald was a notoriously bad speller himself.

If you are as good a writer as Fitzgerald and Hemingway, you can spell however you please.  Why are you paying any attention to me?  Go back to your novel!  But if you’re not, do yourself a favor and learn how to spell.  And learn the rules of grammar, even if you choose to break them.  Clearly I’m still learning.  But this stuff matters.  The site I linked to above says of Hemingway:

Whenever his newspaper editors complained about [his poor spelling], he’d retort, “Well, that’s what you’re hired to correct!”

But editors aren’t doing that anymore!  The editors didn’t pick up the Pulitzer-Prize-winning Harvard English professor’s misspelling of “Ptolemy.”  No one noticed the grammatical errors and the misspelling of “rarefied” in Lisa Randall’s Knocking on Heaven’s Door.  I was looking at the résumé for a technical editor a few months ago, and I noticed he had misspelled the name of the college from which he had graduated.  “Rutgers” just isn’t that hard to get right!  Even when their spelling is OK, some of these editors don’t seem to notice when they use the serial comma in one sentence and don’t use it in the next.  Make up your minds already!  Microsoft Word helps, but notice that its spellchecker wouldn’t have picked up “dint” or “write” in the Hemingway quote.  (It did pick up “Rutgars” though — the “editor” didn’t even bother to spellcheck his own résumé!)

Writers are pretty much on their own nowadays, particularly if they are going the self-publishing route with ebooks.  And that means it’s up to them to get the basics right.  If they don’t bother, they better hope they are as talented as Hemingway and Fitzgerald.