Open System Preferences > Print & (Scan / Fax depending on OS version)
Click the little [+] towards the bottom left of the window to get an "Add Printer" dialog box
Click the IP icon in the top-centre of the wndow and enter the printer's network name, followed by a .bioch.ox.ac.uk e.g. for printer lakp1 you should enter lakp1.bioch.ox.ac.uk
For Protocol, choose HP Jetdirect - Socket. Please note that this is not the usual way of doing things and should only be used for this particular series of printers
Pull down the "Print Using:" selection and choose "Select Printer Software..."
A long list of printers should be visible, enter a search string "1022" to narrow it down. Select "HP LasetJet 1022, 126.96.36.1991" and click OK
Click Add to finish installing your printer