I am doing the same thing with several books myself right now. Self publishing is the way to go and much easier than you think, plus you stay in control of your own work. There are really no guidelines as to how formal or informal you have to be, mainly just adhere to the margins they recommend for placing your text and pics on the pages. Many printing companies offer the do-it-yourself service. You provide the content in a PDF format and they print it for you, its that easy. The pics cannot be in a Jpeg format, they are not high enough resoultion for the printing industry, only 72 DPI, and you need 300 DPI minimum for printing books and magazines, so you have to convert them to another format. You just have to decide what size book you need, 5-1/2 x 8-1/2, 6 x 9 or 8-1/2 x 11, color or black and white pics. You will need to get some specialized software to do the page layouts and cover, you can do the initial layout in Word, but you will need the higher end software like Adobe Photoshop and InDesign to do all final editting and layouts before its ready for hand off to the printer. If your going to be having distribution through a retailer, then you need to apply for an IBSN barcode to identify your book so the scanner can read it, its about $150 to get it. If you need any tips or help let me know. I have one fixing to go to the printer now. I can recommend some printers and give you some ideas on what it costs per book to have it done.
