Find the 3-point hitch on the back of the Bobcat. If the Bobcat doesn't have one, then connect the universal attachment to the Bobcat. There are two parts, the male and female.
Ease the Bobcat universal attachment up to the brush hog. Have a spotter so you can make sure that your alignment is dead-on. If you can't find a spotter, then you need to get out of the Bobcat so you can see how to maneuver so the parts align.
Turn the hydraulic lift on. Push the lever, making the universal attachment go to the ground. As the attachment lowers, you can see when to stop by matching the attachment to the connector on the brush hog. Stop when the alignment is dead on.
Direct the Bobcat's hydraulic lift so that it picks up the brush hog. Drive the Bobcat backwards into the brush hog until you hear the ball grab the hitch. Get out of the Bobcat and fasten the hairpin clips. Thread the flat end through the holes.
Engage the hydraulic lift so that the brush hog lifts off the ground 6 inches and then drive in a pattern, mowing from the outside toward the center of the field.