It is important to stay in a vertical position while descending in diving. If you don't move to a horizontal position when you are at the area that you want to stop going deeper, you will keep going down. It is also important to stay streamlined because you will move much faster through the water column and not be kicked around by currents. It takes time to get used to being in a vertical position and switching to a horizontal position but it will become easier naturally over time.
