Open up Apple System Preferences.
Click Print and Fax.
Click the + sign in the lower left of the Print and Fax window to add a printer.
Click IP.
Select the proper Protocol for your printer type. For HP printers use the Protocol: HP Jetdirect - Socket.
Type in the IP Address or Hostname (example: rosalyn.cc.gatech.edu or 130.207.14.144) of the printer. Leave Queue blank.
Enter in the name of the printer under Name.
Select an appropriate driver under the Print Using dropdown. If you cannot find the correct driver, you can either provide one or use the Generic PostScript Printer driver. Click Add.
You may be presented with an Installable Options screen. If so, select the appropriate options or accept the defaults.
Click Continue to add the printer.