As an author, if I am successful in publishing a book, can I design my own book cover? If yes, are there any conditions or restrictions?

I know an author who wrote a textbook that is used in hundreds of colleges around the world and has made literally millions of dollars for his publishing company. The publisher brings out a new revised edition every 4 years or so. This amazing success story has been going on for about 30 years now.

And the publisher has NEVER taken any of his suggestions for cover art.

So if this guy can't control the cover, you surely can't.

Nope.

Unless you self-publish, and I would STRONGLY recommend commissioning at least legit graphic artist who understands composition and typography. You could alternately commission a piece and have a graphic artist perform the typography.

Regardless, have a proper contract for the nature of the work. (Hire at least a proper para-legal.)

I've been shown potential cover samples at Baen, I've even been shown line art by several house artists (covers for my BATTLETECH work) TOR is not very interested in going that far.

I wouldn't count on it. You might be able to request a specific artist if you follow that sort of thing. Brandon Sanderson got his favorite cover artist to do his cover for The Way of Kings, after he'd been a consistent bestseller for many years.

Lets pretend you've written a great book.

Why would you be so stupid as to think your ability to write extends to the art of selling books?

You now what real professionals do? They let other professionals do their jobs, instead of trying to micromanage everything like a friggin' primadonna.

No.

Unfortunately, you will have no say in your book cover. If you're a best-seller author who has proved their worth over and over they might ask for your input, but until then you just have to like what they give you.

http://lousybookcovers.com/ That is all.