The Skip Labels and Skip Cards functionality is found by bringing up the Print dialog. To bring up the Print dialog, go to the File menu and select Print and then choose Active Output Form from the sub-menu to the right. On the dialog that appears, you will see the button Skip Labels or Skip Cards in the bottom left-hand corner.
Let us use Skip Labels as an example: Skip Labels allows you to mark label positions as the ones you do not want to print on. This is helpful if you have already printed on a page of labels, the page of labels was not entirely used, and you do not want to print on top of the positions of already used labels. Left-click on each label in the sheet that represents a label that has already been used. An X will appear, meaning the program will not print on this position. Repeat to place an X on any other label positions. The program will not print on positions with X's on them. This function only applies to the first page of labels if you are printing multiple sheets.
If you do not have a Skip Cards or Skip Labels button...
This means you have a layout/printout selected that is not a sheet of labels or perforated card stock. These layouts will not have the Skip Labels or Skip Cards option. Not all layouts or printouts have this option available.
If the Skip Labels button is grayed out...
This means that you probably have a "pinfeed" or "tractor feed" label layout selected. If you do, it likely does not support Skip Labels. Skip Labels is only compatible with sheet-based label sheets, and not spooled labels.