Okay so thats a bit of a lie. With these 2 methods the program will open, print the item, and then close the file.
The first way is to select Print in the Finder s File menu. This only works if you have the file selected in the Finder window. For example I have a Numbers document named Bills in my documents folder. If I wanted to print that, with this meted, I would open a Finder window navigate to the file and select it. Go to the Finder File menu and select Print. This will open numbers, print the document, and close the file. It does not close the application though. This method is really solid as long as you only print to one printer because you can only print to the default printer. If you have multiple printers in your environment then you need to try the second method.
Open System Preferences and open the Print & fax dialog. Start dragging the printer icons to the desktop. You can keep the icons on the desktop or if you choice move them to the Dock. When you are ready to print a document then just drag the file from a Finder window to the printer icon you want to have print the document.
If you are going to use the first method then I would suggest adding a keyboard shortcut to make this even faster. To do this open up your System Preferences and navigate to the Keyboard & Mouse dialog. Select the Keyboard Shortcuts and click the “+” button. this will open a new window. Fill out out with the same setting in the picture. Application = Finder, Menu Title = Print and then click on the Keyboard Short care area and type what you want to use. I used command+p. Click Add and you are in business. Now all you need to do is select the file in the Finder and press command+p and the default printer will print out your document.