Address Labels in iWork
If you want a sheet of labels all the same, Pages is best for this.
1. DL the appropriate Avery label template (in Word) from the Avery website
2. Open it in Pages
3. Make one label using Menu > Insert > Merge Field/Sender Field
Merge is information from someone NOT you, Sender Field is YOU.
4. Copy and paste that merge set into the other label Textboxes on the page
5. Save as a template
Merge works by you dragging the VCard of your choice from Address Book onto your page document
Sender works by looking up what is on your own VCard, the one with the head & shoulders icon on it.
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