Cutting down a Christmas tree requires proper technique and safety precautions. First, select a healthy, straight tree with a trunk diameter that fits into your stand or tree holder. Next, use a handsaw or chainsaw to cut down the tree at a 45-degree angle. Once the tree is on the ground, make a second cut at the base of the trunk, cutting at a 90-degree angle to the ground. Finally, tie the tree to a vehicle or cart for transportation and secure it for stability during travel.