Being your own publisher
For many reasons you may not be ready to go to a publisher to produce your book and make it available to a wider audience. But you can still get your book "out there" in physical form by becoming your own publisher!
Armed with a laser printer and a long stapler it is possible to desktop publish small pamphlets up to about 64 pages, which might be sufficient for a small user manual, specialist publication or collection of poetry. This is a feasible approach up to about 100 copies, but be prepared for some extremely hard work. Beyond this number you will certainly want to use the services of a printer. Even the most basic of local printers can easily produce this kind of material with too much cost.
For larger publications you will probably want "perfect bound" or "saddle stitch" books, which requires more specialist equipment. This is beyond desktop equipment, but most local printers will be able to do this. However at this level you should also consider using a specialist book printer.
Self-publishing may seem a very attractive idea, especially as you get to keep most of the sale price of the book! However, one has to be realistic - it can be expensive to go directly to a printer and you will have to do all the hard work of promoting and selling your book. Donņt expect to get much help from the book-selling industry - for the most part they are very wary of self-published work. And many self-publishers have ended up with garages or spare bedrooms filled with unsold stock.
However, over the last decade or so new Print On Demand or POD technology has revolutionized the process of self-publishing. It is now possible to get your work printed in small quantities, in some cases only a single copy, with minimal or even zero setup cost. This means that you only need to pay for books that are actually sold, and there is no need to keep stock. It is even possible to have POD books with an ISBN number and an Amazon listing. This opens up self-publishing as a low-risk way of getting your work into print.