Perhaps find a tree feller that works for a logging company. I've taught myself and have had no incidents for the previous eight years. Although, I don't cut many trees each year. This year will be the most so far, about eight. The early years of experience involved trees that did not represent a hazardous path to drop. No buildings, or possibility of a snag. I began watching youtube videos and that helped a lot. I would recommend them as they provide information you may not considered cause you don't know what you don't know. This particularly applies to tree felling.
Depending on the type of tree involved, and it's lean, or entanglement, cutting trees down can be very dangerous. Anything from an improper cut that causes the tree to split up the middle and whack you in the head with the base, to what is known as a Barber pole where it splits with a twisting motion.
Tools:
Prior to any cutting, check your work area and exit path for debris, fencing, anything that will impede a rapid exit from the area once the tree begins to fall. Be sure to look up into the tree for any dangling branches that may fall when you begin to cut.
I presently use wedges and a 3/4 ton come along when there is only a slight difference between the direction I want the tree to go in, and the direction the tree want to fall. However, since I can't get more than a 10 foot ladder height up to attache the chain, there is not much of a mechanical advantage. Enough though if there is not too much lean.
I would earnestly recommend you find someone affordable to do the work and teach you the basics the first time around. There is a lot to this and I haven't even started on the chainsaw. I'll post more later. For now, here are some videos I've watched:
