Some laser printers may need the paper type adjusting. This is because some laser printers assume that all paper is 80gsm and they don't heat up the paper enough for the toner to adhere to the paper's label area sufficiently. Some printers have a setting for a paper type of Heavy (90 - 105 g/m2) others have a paper type of Labels.
If your printer needs to pickup the labels from the non-label end you can flip the output by 180 degrees in the printer options.
Examples are shown below:
Some printers also need adjustments so that the relevant text appears on the label. An example is shown below: