While engineering the room, not only will seam placement be planned, but also the location of the mismatch - where the final strip to be hung will be butted up to another strip and the pattern does not match. Two factors affect this decision: the pattern of the wallcovering and the architectural layout of the room.
If hanging an entire room, choose the place where the partial strip will butt against a full strip, or where the mismatch will be most inconspicuous. Choose a short area of wall to place the mismatch, instead of having the mismatch be the length of an entire wall. The ideal place in most occasions is over a door or window that is not on the focal wall. There are times when the mismatch will be best placed in the corner behind a door, even though that will yield a mismatch the length of the wall.
A natural breaking place such as floor-to-ceiling fireplace can eliminate a mismatch, but only if the pattern being hung does not contain large design elements. If there are large design elements, the pattern needs to be hung with the main part of the design element symmetrical on each side of the breaking point, and then hang the walls going both right and left, planning where the mismatch will land.
After the mismatch point has been designated, decide where to start hanging based on seam placement from the engineering. It is possible to start in the middle of a wall and work in two different directions to the mismatch point.
Content Provided by the Wallcoverings Association (WA).