The Lilypad scale consists of 4 weighing pads, held in place by a mat. Make sure all your weight is on the weighing platform part of the pads. You can view your weight on your smartphone or tablet with the Lilypad app.
Each pad consists of a weighing platform, which is the black metal part in the center, ramps on either side, and the green guide rails. The pads can be rolled onto from either direction, but you should avoid rolling on top of the guide rails as this could damage the pad.
To see the parts of the weighing pads in real life, check out this video: