The thing that confuses everyone is that this system provides a fixed coordinate reference ( celestial longitude) for objects, but at the same time it rotates across the sky one full lap every 24 hours. To use it, you have to determine your 'Local Sidereal Time' by, for instance, visiting the US Naval Observatory and knowing your longitude. This LST represents the Right Ascension 'meridian' which passes from the south celestial pole, through your local zenith, and connects with the north celestial pole near Polaris. Once you know, for a particular time at night, what the LST is, then you can subtract this from the Right Ascension of your object to determine how far to the east or west of your local meridian the object is. For every 'hour' of LST-RA difference, add 15 degrees. You have to repeat this calculation EVERY MINUTE because the sky rotates.