Make a fresh cut across the base of your tree before placing it in water.  A fresh cut is one less than 6 hours old.  1/4" or more must be removed to make a fresh cut. 

Keep the tree base in water continuously once you bring it inside.

Store the tree in a sheltered, unheated area (i.e. porch or garage) to keep it dormant.  

Store pre-drilled trees on your Yule stand with water added right away. If necessary, 1/4" can be cut from the base of a drilled tree without affecting stand ability.

Your tree will be "thirsty", especially the first day it is inside.  Allowing the water to run out may cause a seal to form, interfering with
further water uptake.  You may need to fill your stand twice a day for the first few days.

Keep tree away from heat sources including radiators, forced air vents, TV's, fireplaces. Check electric lights and connections. Do not use lights with frayed cords. Turn off tree lights when you leave or retire at night.

Never use combustible decorations or lighted candles.