Empty your cabinet of all shelves and items. Test fit the mechanical system to make sure it fits inside your cabinet. There are several manufacturers of this type of system, and each one will mount differently. Follow the directions exactly for your model so that the mechanism is mounted properly and will not fail.
Mark the location of studs on the inside of the cabinet back wall. Mark the location of installation brackets. If your cabinet is made of inferior cardboard or fiberboard products, you should replace the cabinet with solid wood prior to fitting the cabinet with the mechanism. Some lower grades of cabinets may not be rated for the weight or stresses of the mechanism.
Screw or bolt the mechanism into the inside of the cabinet. Some units mount to the top and bottom of the cabinet while others may secure through the back wall or by other means. Use the hardware and fasteners provided by the manufacturer for the best results.
Adjust the height of the pull-down handle and shelves after the unit is installed. Often the shelves and accessories are sold separately, allowing you to pick the exact type of shelving you need. The handle should be low enough for easy accessibility. The doors of the cabinet should have hardware that is equally easy to grasp and open.