Buy a tree that is not too big for your room.
Don’t place the tree too close to curtains or other easily flammable stuff.
Don’t place the tree too close to heat sources such as television, fireplace and/or radiators.
Make sure the tree is established firmly so it can not be overturned. If you use a wooden cross and you want to put the tree right ,then put a foot on the cross and push the tree in a single move upright. You will find a manual here.
Place the tree preferably in a christmas tree stand filled with water. This keeps the tree from drying out to quickly and reduces the risk of fire.
Do not use real candles for the tree. One moment of oversight can turn your tree into a torch.
Check the wiring of electric christmas tree lights for damage and try them out by letting them burn for a little while before putting them in the tree.
Use a well-fitted extension cord in good order and place it so that no one can trip over it.
Turn off the lights when you go to bed or leave the house ( ‘taking off’ means to unplug the cord, not by unscrewing a light bulb).
To clarify here an overview of the sizes of Christmas trees. Very often people buy a tree of 4 meters, but apparently have no idea how impressive (and spatial) such a tree is. That’s a shame.
As a rule, you can assume that a christmas tree is about as wide as it is long! A normal living space is usually not more than 2.5 meters high.