When defining your target audience, consider these points:

1. Your audience is probably not as broad as you think. Avoid statements like “all programmers,” or the simple “web developers.”
2. Tell me what your audience already knows, or what prerequisite knowledge must they have before they tackle your subject.
3. Tell me what your audience wants to do, or how they will benefit from your book.
4. If possible, break the audience down into at least 2 camps – the primary audience, and secondary audience and what each will get from your work.

For example:

Professional XNA Game Programming is for readers who want to use their existing programming skills to create games for the Xbox 360 and Windows platforms. It is intended for readers with previous experience with C# or a similar .NET language, although no game programming experience is required.  Readers with experience using DirectX will find that it proves useful in tackling the 3D portions of the book, although it is not required.

(Photo credit: jambe)

Many of these details are estimates at the proposal stage, but take the time to seriously consider them. Never send me a proposal with these details flagged as “unknown.” Here is a list of items to include in the Manuscript Details section of your book proposal:

1. Page count – this is critical, and one that I too often see listed as “unknown.” If you are serious about your book, then you must have an idea as to how long it will be. Until the manuscript is edited and composed, of course we don’t know exactly how many pages it will be, but give me something to work with. Is it about 200 pages, 600, 1000? Consider how long similar books are – will yours be shorter because your approach is distilled, or will it be longer because you want to provide more detail than current titles? You should be able to get a fair estimate if you include page counts per chapter in your outline. (more on that in a later post)
2. Expected completion date – I need to know when I can publish this book should it be approved. How will I know? Well, I know how long it takes our group to take a book from complete manuscript to shelf, so knowing when you are going to be done is where I start counting. I might want to target a particular buying/selling period or make a book available for an event or time it to a software release, so getting you to commit to a due date is important.
3. Images – what types of images should I expect to find in your book? Are they all screeshots, or will there be some tables, charts, or other illustrations? How many do you expect? If you are unsure how to estimate, you might think about comparable books and how many images they have – one every few pages, every page, etc. The number of illustrations is particularly important since if we are going to be creating some of the images from your sketches we will need to schedule that time with our illustrators.
4. Hardware and software used – you wont find this on all types of proposals, but we ask for it on our tech books. I need to know what software you will be working with to be sure its compatible with our editing and production processes. In many cases your publisher will ask you to use a particular program. (In our case it is MS Word and our templates.)