1. Choose position of clamps, based on pannier rack hoop and according to what you will use Side rack plate for. Different mounting positions are possible. It is preferred that two clamps are on top side, two on bottom and one at each side.
2. Shown below is proper way to insert clamps - "flat" part is on the inside, so Side rack plate will fit inside the hoop. Compress each clamp, so it will be easier to install Side rack plate.
3.Secure upper clamps first, in "tilted up" position. This way you can easily engage bolts and washers and than just tilt the plate downwards.