On one side of your base cabinet, measure and mark out where you will be drilling the holes to attach the drawer runners and the lid holder. You'll find these measurements in the instruction book that comes with your kit.
Use a spirit level to draw lines from the back of the cabinet to the front, so that you know the holes you're drilling are in a straight line. Once you marked where you need to drill, pre-drill the holes using a small drill bit. Repeat this process for the other side.
Before you attach the drawer runner, you have to separate the side brackets. The trick is to pull it forward, all the way out, and look for a black lever in the middle, which you flip so that the mechanism comes apart.
Screw the bracket components of the drawer runner and lid holder onto the inside sidewall of the cabinet, making sure the screws are tight. Remember, the lid holder will be attached above the drawer runner. Then turn the cabinet over and repeat this process on the opposite inside wall.
After attaching the brackets, stand the cabinet up and slide the drawer runners into their corresponding brackets. You should hear a click when the runners are in position. Now insert the bin lid frame between the brackets and screw it down. Then put the bin lid on.
Now line up the brackets to your marks and fix them to the inside of the front panel with your screws. You will use these brackets to attach the front panel to the basket.
Fix the front panel to the basket using the screws provided. The slots for fixing the panels are longer so that you can adjust the door later.