There is an online tool from Avery to make labels, too.
I prefer the desktop version
https://www.avery.com/software/design-and-print/desktop
Occasionally I need it to create templates for address label numbers that I don't have physically available.
Even without that Avery app, it should work (tested with macOS Sierra 10.12.)
-> in Contacts.app -> Select the addresses to print -> File -> Print… -> Show Details -> Style: Mailing Labels
-> Layout -> Page: choose Avery Standard or Avery A4 and see if the needed template is existing
-> If not, select Page: Define Custom… and setup the label template that you need
I'm thinking about buying a Dymo label writer or a similar special label printer, but as I use windowed envelopes and a stamp for my address, I just need labels every now and then. For that occasions I started to utilise whole sheet stickers that I can cut anywhere to sizes that I need. Usually I make these labels with InDesign or they are already existing PDFs.