Our wallpapers are sold with margins, which means the have a white area on each side.
This requires a particular laying technique, which gives you the advantage of assuring perfect pattern match.
Each side also has an overlay area where the pattern of the right and left side are common.
(if the previous strip is on the left hand-side, cut the margin to the left).
Do not worry if your cut is not very accurate. The point is to completely remove the margin even if you also cut a few milimeters of the printed area.
After applying the paste onto the wall, display your stripe so the the parttern matches the previous stripe.
You'll note that the stripes overlay.
Cut the overlaying area with a Stanley Knife.
Even if your cut isn't perfectly straight, the stripes will still match.
All you need to do is remove the excess paper. Your two stripes side are perfectly matching.