Make sure that no seam is placed perpendicular to doorway or immediately across entrances, except for doorways. Make sure that the carpet is laid perpendicular to the cushion seams. Where this cannot happen, make sure that cushion seams are at least six inches away from carpet seams. Make sure that your carpet is power stretched with a power stretcher. No power stretching can lead to buckling and delamination.
Power Stretchers are long pole apparatus with teeth.
Make sure that the cushion seams are taped. If the tape is not in place, then gaps can form in the cushion seam making a dark line in the carpet. Make sure that all carpet seams have a seaming adhesive applied to the cut edges. Seam sealers generally have ultra-violet dyes that will shine under a black light. If no seaming adhesive is applied this can lead to fray edges and pulled loops in the seam.