From the main screen choose the Administration Tab and then select "Add Printer" You will be prompted for a username and password - enter your normal pi username and password, or whatever user you added to the lpadmin group earlier.
Select the one marked "EPSON" and choose continue If you only have one printer the fields can usually be left at their defaults.
An alternative is to setup a pass through printer which lets the client handle the print filters.
Choosing continue and it will then take a little while to search for the printer.
It may be useful to change these if you are setting up a print server for a company network that has multiple printers, or you can change them for your own benefit if you prefer to use a different name.
The one field that you may consider if you have local printer is the "Sharing" option.