To set up a set up an HP Photosmart C4780 printer for wireless printing, visit the HP website, and install the provided driver and software. During the installation process, the software requires for you to select a connection type; choose the wireless connection from the list.
Check the connections for both the computer and printer prior to setting up the printer. Make sure you have the network name, which is the SSID, and the network password, which is the WEP key or WPA security password. It is recommended that your Internet access is established through either a cable or DSL connection. Verify that the printer, router and computer are turned on, and connect your computer to the wireless network. Disconnect cables from the printer, and install the driver. Connect the USB cable between the printer and computer; this provides information to the printer from the computer. If you have an installation CD, use that instead to install the software.
To download the correct software and driver, go to HP.com, visit HP Customer Support section, and select Software and Driver Downloads. Find your printer model, and follow the instructions on the page to access the download section. Select the Download button, or visit the Basic Drivers page for additional drivers. For a download guide, use the HP Download and Install Assistant.