Okay, here is what you do:
Firstly, you get some bleach, gloves, some sort of weapon (a knife preferably), and some citric acid.
1: You find out where he lives, wait until he is alone(preferably sleeping) , put the gloves on, bring the bleach and the knife. Cut his throat. Bring the body to your house in some way, poor bleach on the blood, take one of his animals, and kill it where you killed him(to disguise he is missing, like he just went out/ran away)
2: (This helps if you live alone/have some place no one goes to). Put the body over a bathtub. Cut the major arteries(check google, not going to hold you hand all the way through this) and make sure the blood is draining, this helps clear the stench and to help the body decompose.
3: When it is drained, cut the corpse into pieces, and lay them out and poor the acid onto them (this may take a couple of days) To get rid of the flesh and things, it might dissolve the bone if you leave it in there long enough.
4: Discard the remnants into separate containers nowhere near your house, nor each other.
5: You just committed murder!
Make sure to where the gloves ALL THE TIME
Don't get caught.
Don't do any thing stupid.