Sometimes the best inspiration for writing comes from those who have actually proven themselves to be effective and successful writers. They are proof that "if they did it, you can too--with the right effort and motivation. For example, consider the following quotations.
A scrupulous writer, in every sentence that he writes, will ask himself at least four questions, thus: What am I trying to say? What words will express it? What image or idiom will make it clearer? Is this image fresh enough to have an effect? And he will probably ask himself two more: Could I put it more shortly? Have I said anything that is avoidably ugly? (George Orwell)
It's not wise to violate the rules until you know how to observe them. (T.S. Eliot)
You can't wait for inspiration. You have to go after it with a club. (Jack London)
Always dream and shoot higher than you know you can do. Don't bother just to be better than your contemporaries or predecessors. Try to be better than yourself. (William Faulkner)
The best writing is rewriting. (E.B. White)
Only writing will make you a writer. (James K. Van Fleet)
Pay no attention to what the critics say. A statue has never been erected in honor of a critic. (Jean Sibelius)
Now, get busy with your own writing! If they could do it, you can too!