Click on the Start Button and find "Devices and Printers" on the right menu panel. Then click on the Add a Printer button

Choose "Add a local printer" (unless you specifically understand about network installations) and then choose the port you will use to connect your printer.

It is most likely you will use the existing "LPT1" port (parallel port). If you want to use a USB to parallel converter, you should do this BEFORE you start the add printer routine and then make a note of the USB port it has created for the USB to parallel converter.

The Add Printer box will then show the printer models available. Scroll down and click on Citizen.

The printer driver you require may not be shown immediately. You must click on Windows Update to scan for new drivers. This process can take 5 minutes to download the list of drivers available.

Once you have done this, you can find the printers available from Microsoft directly. The following are currently shown in Windows 7 update:

Citizen 120D+, Citizen Printiva 600C, Citizen Swift 240 ESC/P2, Citizen Swift 240x ESC/P2,
Citizen Swift 9, Citizen Swift 9x, Citizen GSX-190, Citizen GSX-240 ESC/P2, Citizen GSX-245 ESC/P2

Citizen CD-S501/503, Citizen CT-S2000, Citizen CT-S280, Citizen CT-S281, Citizen CT-S300
Citizen CT-S300 Black Mark, Citizen CT-S310, Citizen CT-S4000 Label
Citizen CT-S601, Citizen CT-S651, Citizen CT-S801, Citizen CT-S851
Citizen PPU-700, Citizen CBM1000 Type II, Citizen BD2-2220/2221