Some blimps have some kind of propellers that can get the blimp close to the ground. When the blimp is close enough to the ground people on the ground grab and pull the ropes while the blimp's pilot maneuvers the blimp until the ground crew is able anchor it.
They gradually cool the air that is holding them up when they near their landing point. Once they are near the ground, they lower lines to crewpeople on the ground, who guide the blimp down the last little bit of the way.
Blimps have lines that can extend from the nose and tail of the blimp that are lowered to the ground crew. Those lines are used to pull the blimp down.
