Keep the tree stand filled with water. A seal of dried sap will form over the cut stump in four to six hours if the water drops below the base of the tree, preventing the tree from absorbing water later when the tree stand is refilled. If a seal does form, another fresh cut will need to be made. A tree will absorb as much as a gallon of water or more in the first 24 hours and one or more quarts a day thereafter. Water is important because it prevents the needles from drying and dropping off and the boughs from drooping.
Water also keeps the tree fragrant.
In addition, keep your tree away from heat and draft sources like fireplaces, radiators and television sets. Test your light cords and connections before hanging them on the tree to make sure they're in good working order. You don't want to use cords with cracked insulation or broken or empty sockets. Also be sure to unplug the lights before you go to bed or leave the house. Never overload electrical circuits.