CreateSpace offers free Microsoft Word templates based on your catalog's trim size. You'll have to visit the Community text link> Resources > Formatting Your files > Documents and then look for Interior Templates. You may need to have joined CreateSpace to download one of the templates.
If you set up your own Word file, you can play with the following settings:
- Paper size - make 7 x 10 inches or 8.5 x 8.5 inches
- Font - I like the Georgia font - it is very readable
- Font size - this is your personal preference... just make it readable, maybe 11 or 12
- Margins: try experimenting with Top 1 inch, Bottom 1 inch, Inside .75 inches, outside .75 inches, and Gutter (this is that valley in the center of a book) .25 inches
- Justification - I prefer left and right justification. This is where the text spreads across from left to right vs having a jagged right edge.