The springs extend along the shaft and work by twisting as the garage door closes by means of cables attached to each side of the lowest garage door panel.
How to install a garage door side spring.
There are two types of garage door springs.
Use locking pliers or a c clamp to secure the door to the track to keep it from opening when you release the tension on the springs.
Side mounted springs are long heavy springs mounted on each side of the upper garage door track.
Unplug the garage door opener and clamp the door to the track.
A couple of carabiners can.
Disconnect the garage door opener so the door remains closed.