If you have the labels, you should be able to create a label template like this:
1) Set page layout to portrait
2) Measure the margins of the sheet of labels and set the page margins to that.
3) Delete the default table and insert a new, plain table.
4) Make the size of the table match the layout of the labels. If the labels are 3 columns of 10 labels each then the table will be 3 columns x 10 rows.
5) Go to Print view
6) Select the table in the sidebar. The table will get little squares on each corner.
7) Drag the corners to the edges of the paper but not so far that the table spills onto other pages.
8) Select all the cells of the table (all at once, not one at a time) and format them however you want.
You can use formulas in this template that can pull data (name, address, etc.) from other tables.
Did this answer the question? It wasn't clear what you needed to be able to do other than print on labels. If you don't need to do something that requires using Numbers, Pages might be a better solution for label printing. Templates are available for Pages and can be imported from Word.
