The best way to adjust our bands is before you put them on. The oval shape is comfortable for most people, but it depends on the shape of your wrist. 

Start from the right side, and squeeze the edge of the bracelet upward. Do the same with the left side. When you adjust it this way, the edges of the bracelet will get closer to each other, and the shape of the bracelet will be oval, without creating the bump in the middle. Leave enough opening, about the size of the height of your wrist, so you can easily slide it on. Once the bracelet is on your wrist, squeeze it just a little bit for the perfect fit.