1.) When you are hanging a large scale pattern in a room that has a fireplace, center the first strip over the fireplace and hang to the right.  Then go back and hang to the left.  If you’re going around the whole room, plane to end in an inconspicuous corner.  Make sure you plumb the first piece to ensure a perfect line.
2.) Never “wrap” a whole strip around inside corners without cutting and  re-aligning.  It may look okay at first, but in a few weeks, wrinkles and creases may appear.
3.) When using no-match, plain textured wallcoverings, reverse every other strip top to bottom for uniform colour.
4.) Check the run numbers on your rolls before you start to make sure they’re the same, as colour may very slightly from run to run.
5.) Where vinyl wallcoverings overlap corners, ceilings etc. you’ll need a vinyl adhesive to stick them together.
6.) Never use a seam roller on blown vinyls.  Gently tap the seams with the edge of a smoothing tool.
7.) If you’re not going to paper the inside of an arch or frameless window or door, trim the wallcovering with your razor 1/4” from the outside edge.  This will prevent fraying or pulling.
8.) Ceilings like walls, are not always “true”.  Plan to end the ceiling wallcovering on the less critical side of the room, like above the entrance.
9.) When using the same pattern on the ceiling and walls, it can only be matched one way. So choose the direction most frequently looked at.  To match the pattern, trim the ceiling wallcovering so there is a ¼” overlap on the sidewall.  Match the first sidewall strip at the ceiling line, overlapping 2” as usual.  Smooth the strip down.  To trim the overlap, score it with a pencil at the joint.  Pull the wallcovering back and cut on the scored line with scissors.  Smooth it back down.
10.) Be sure you size your surfaces before you start wallpapering.  Wall prep makes the job successful.