Go to the "Apple Menu" in the upper left corner of your computer, then select "System Preferences."  Find the "Printers & Scanners" System Preference.

In the "Printers & Scanners" System Preference pane, select the printer that you would like to delete, then select the "-" symbol.  Please see the picture below.

When you select the "-" button, you will be prompted for a confirmation that you would like to delete the printer.

Select "Delete Printer" to remove the printer.