To make a Christmas tree last longer, there are a few things you can do. First, make sure to buy a fresh tree with plenty of green needles that are not dry or brittle. Next, you should cut off a few inches from the base of the tree to ensure that it can take in water properly. You should also make sure to keep the tree watered regularly, as this will help keep the needles from drying out. Finally, you should keep your tree away from heat sources and direct sunlight, as this can cause it to dry out more quickly.