Whether you're an Indie author or traditional publishing author, there are always things that can be improved. When looking at any writing product, the one thing that always jumps out is the editing or lack of editing. Some writers are lucky to have someone else edit their work (I do editing for for some) but some have to edit their own work (I edit my own). I have put together some tips, not just for editing and format, but writing in general. I will be referring to the writing work as "the project".
Read. Once the first draft is completed, go back and read the project. Ask yourself questions. Does it make sense? Are there things that should be removed or added?
Read. Read it again after any changes.
Edit. Edit. Edit. Make sure that you use the word processing software's built-in spelling and grammar check.
Read every word. Read the the project out loud.
Listen. Use a read-aloud software on your computer to read the project, and listen to each word. (MS Word has this feature, but only a limited of text at a time) (Convert to PDF and have Acrobat Reader read it to you).
Edit in print copy. Yes, print out the project and read it. Work in print is easier to point out mistakes and errors.
Read in intended format. For example, if you're converting your book into a mobi (kindle format), convert it and load it on your Kindle or Kindle app, then read it.
Final draft. When you are satisfied with your final draft, leave it alone and walk away.
After a little space, read your final draft. Then, deem it finished.
Format. Follow the formatting guidelines for the appropriate format. (If you're using Amazon Digital Publishing services (Kindle), make sure you format with appropriate tab settings and space. If you manually use tabs with the tab key, expect a double tab to appear in the kindle).
Covers. If you are not artistically inclined, have someone create the cover, or use one of many different online cover creators. The cover should draw attention to your project and tell a story about the project.
Do not use the words "a novel" after the title of your project, or anything else that would describe it. If it's a novel, the reader will know it, you don't have to tell them.
Line spacing: Use appropriate line spacing, so that when the project is formatted, it is not too much spacing or too little. (I personally use 1.20 spacing, as I think 1.50 or 2.0 is too much, and a single spacing is too crammed).
Synopsis: Don't write synopsis or book blurb until the project is finished. This will appear on the back cover of a print copy and in the description of a digital format. Don't make it too simple, and don't make it too in-depth. Too many times authors write a synopsis that tells the entire story line. Why read a book when the synopsis tells the entire story?
Reviews. If you can get your project out to book reviewers before it's released, do it. Be aware of the reviewer's policy, especially on genre types. As a book reviewer of all genres, I also have a detailed policy I expect to be read.
Reviews. Not all reviews are going to be 5 stars, or even 4 stars. Not all reviews are going to be kind or intuitive, but the ones that are, for good or bad, read and use them as a learning tool. Even the greatest writers have had bad reviews. Can't please everyone.
Read. Not your own work, but take the time to read other authors, not just your favorite authors, but other indie authors.
Writing style. Everyone has their own writing style, and sometimes we can improve upon our writing. Some don't like my style and others love it. It's a matter of preference.
Reading preference: Take what you like and don't like about others' works, and utilize it in your own writing. I personally like some details, but not a detail about every little thing, as i like using my imagination when reading.
These are my tips, and are only my opinion. I am an Indie Author and have had work published POD publishing. I do editing. I help with formatting. I also review books.