I guess they figure a buyer has some experience or usage is intuitive.
Your tractor manual should discuss the 3 Point Hitch to a degree. The two lower links (draft links) actually do the lifting part. The upper link (top link) helps stabilize the implement your are using when hooked to the upper connection of the implement you are using.
For example, your rotary cutter should have two pins approximately 3/4" in diameter and about 4" long. The are horizontal. Your lower links (with the ball eye bushings) connect here.
There should be an upper bracket that probably swings. The upper (top) link connects here. For use, you thread out the link so that bracket on the cutter can follow the ground contours. For transport, you tighten (shorten) the upper link as much as possible...by hand. There is a jam nut on the threads of the upper link closest to the tractor end. I just run it up by hand, but I don't transport my implements too far. Once tightened, you can raise your cutter, but don't raise it high enough to have the PTO shaft riding on the front end of the cutter.
Also, by tightening or loosening the upper link, you can raise or lower the front end of the implement somewhat. For a rear blade, this makes for a more or lesser aggressive "bite" in the soil.
To hook up the cutter, have the tractor engine off with the key in your pocket (in YOUR pocket!). Hook the lower links to the pins on the cutter and install the lynch pins in the holes (on the cutter pins) outboard the tractor's lower links.
Then, hook up the PTO shaft. If you look at the tractor's PTO, you'll see a groove machined circumferentially on the PTO. The implement PTO shaft will have a mechanism that locks in that groove. The PTO shaft will have a spring loaded button or ring on the tractor end "U" joint. Depress that button (or rotate the ring) and push the "U" joint on the tractor's PTO. Once the splines are lined up, let go the button (or ring) and push toward the tractor until you here the shaft's locking mechanism lock into place. Pull back on the shaft to ensure it's locked in place.
Rotary cutters don't have front wheels, so I suggest you have some kind of lever handy to jack it around a bit to get everything lined up.
Now, this may sound complicated, but with a few tries it'll take you less time to rig up an implement then it did for you to read this.
Good luck!