How To Do Desktop Publishing and Desktop Printing

1. Have a Plan, Make a Sketch. Before even opening the software it is wise to have an idea where you are going with your design. Even the roughest of sketches can be useful...
You could skip this step but I recommend trying to do a fewthumbnail sketches first.

2. Choose a Template. If your chosen software has templates for the type of project you plan to do - take a look at those templates to see if they will work as-is or with a little tweaking for.
your project.Using a template can be faster than starting from scratch and a great way for those new to desktop publishing to get started.

3. Set Up Your Document. If using a template, you may need to tweak some of the template settings. If starting from scratch, set the size and orientation of your document. Set the margins. If you'll be doing text in columns, set up text columns. The specific steps you take in the document setup will vary from one type of project to the next.

4. Place Text in Your Document. If your document is mostly text, place it in your layout by importing it from a file, copying it from another program, or typing it directly in your program (not the best choice if it is a substantial amount of text). 

5. Format Your Text. Align your text. Apply the desired typeface, style, size, and spacing to your text. You may end up making some changes later, but go ahead and select the fonts you believe you want to use. Apply embellishments such as plain or fancy drop caps. The specific steps of composing textthat you choose will depend on the amount of text and the type of document you are preparing.

6. Place Graphics in Your Document. If your document is mostly graphics-based, you may want to place the images before adding bits of text. Import your graphics from a file, copy them from another program, or create them directly in your page layout software (simple boxes, rules, etc.).

7. Tweak Your Graphics Placement. Move your graphics around so that they line up the way you want them. Set up your graphics so that text wraps around them. Crop or resize graphics if necessary (best done in your graphics software but for desktop printing it can be acceptable to crop and resize in the desktop publishing software).

8. Apply the Rules of Desktop Publishing. Once you have your initial layout, improve and fine-tune. Simply applying these tried and true methods of arranging a page and doing desktop publishing ("the rules") will result in more attractive pages even without formal graphic design training. In brief: drop typewritten conventions such as two spaces after periods and double hard returns between paragraphs; use fewer fonts, less clip art; leave white space in the layout; avoid most centered and justified text.

9. Print a Draft and Proofread It. You can proofread on screen but it's always a good idea to print out your project. Proof your printout not only for colors (colors on screen don't always print as expected) typographical errors and placement of elements but if it is to be folded or trimmed, make sure it folds properly and that trim marks print correctly. Think you've caught all the errors? Proofread it again. 10. Print Your Project. Once you're happy with your layout and your proofs are printing properly, print your creation on your desktop printer. Ideally, even before you finalize your design you've gone through all the preparatory steps for desktop printing including calibration, print options, previews, and troubleshooting.

Source: http://desktoppub.about.com