The only pruning that should be done is snipping off brown tips and dead branches. Brown tips will never turn back to green, and unfortunately, once they have turned brown, growth will stop from that point. Norfolks resent replanting, so they should only be repotted every 3-4 years , in the spring. Use a fast-draining, sterile, commercial potting soil mix. Should you decide to decorate and use your Norfolk as a Christmas tree, be sure that the soil is kept sufficiently moist during that time when it is decorated.
Lights have a severe drying effect on plants.