To use them, just cut out the tags, wet the back of the wallpaper/tag and adhere them to your holiday packages, gift bags, letters etc. etc.
Or for sturdier tags adhere the wallpaper to card stock, let them dry flat and then cut apart.
Many designs from this collection can be seen here: http://www.spoonflower.com/collections/37094
Wallpaper Coverage Calculator
Based on the dimensions you provide, this calculator will determine the number of custom-length sections of paper you'll need to cover any surface. If the height of your surface varies, input the tallest dimension in order for the pattern to line up correctly.
Enter your dimensions in feet (1 foot is 30.48 cm).