You should be sure of its condition before you choose to fell a tree. You can do this by walking around it and determining the weight of its limbs based on the location of where the tree top is falling and how they're dispersed. If you want more information about tree trimming you can go http://www.treekingofli.com/tree-pruning/.
You always need to check for oddities bark cracks in the tree or that comes from the tree itself. The process can influence rather than assess the tree is dangerous. You should also know about other trees in the area and be aware of whether or not the branches from these trees will interfere with the one you're currently cutting.
The next step is to determine which direction you want the tree's branches as soon as you have that you can work with that will not cause any harm to the land. The direction is the one that's near the tree's lean.
Make certain to pick the flattest surface possible as soon as the floor is irregular the branches may break as soon as they're cut down, or roll and pose a risk. Use a ladder so as to secure it that it's more likely to drop in the ideal direction if you're going to take out the tree thoroughly.
So as to cut at a way through the 21, another suggestion is to use a chainsaw. Make another cut to make a notch you have made after doing so. The mouth of the notch will be set that you're thinking about felling the tree.