Here's what I do when I write sales letters and ebook...

1) INCREASE YOUR CAFFEINE INTAKE -- Okay, so I'm caffeine junky. I'm talking loads of it. Of course if you don't drink caffeine currently, I wouldn't recommend getting started.

But if you do enjoy a good cup of Jo or a soda here and there, then try using it before writing. Studies have shown that it actually increases your IQ points. And I find coffee is a great way to "oil" my mind and fingers for writing quickly while increasing my clarity.

2) RESEARCH YOUR WRITING PROJECT -- Read everything you can on the subject right before you start.

If you're creating an ebook, look at other books on a similar subject. Same with sales letters. Read all you can. And the best way to absorb it and use what you find is to read about it moments before you actually start to write.

3) NOODLE YOUR IDEAS AROUND --After researching I like to sit back and think about the subject.

And when I do, I notice new ideas that pop into my head like magic. Then it's time to start taking notes so I don't lose an ounce of inspiration.

4) START TO WRITE -- Beginning to write for me is like dipping my big toe into a pool before diving in.

I like to start writing whatever comes to mind so I can center in on the subject. With sales letters I start working on headlines and openings. And sometimes I'll start over a hundred times or more. It's a warm up for writing, and it lets me try out different ways to best communicate. Same with ebook I write chapter by chapter. I get ready, start writing a chapter, and I might do it over a dozen times as a warm up. I write like this until I'm like a horse eager to get out of the gate. And then I just let my writing take over -- once I'm warm -- and start a marathon writing cycle.

5) WRITE FAST --Writing fast does wonders for the work you produce.

By writing fast you'll have a more continuous flow and that makes for an easy read. Sentences ideas paragraphs all blend together perfectly when you just write what you think and stop for nothing.
Don't worry about mistakes or things that don't seem right as you're writing them. Just keep plugging along. Get that first draft out, let it settle, and then go back and clean it up later.