You need a theodolite and a clock. From a map of the Earth, you need to accurately know your latitude and longitude. The theodolite measures the elevation of the star above your local horizon. The declination of the star is the angle between the Celestial Equator and the North Celestial Pole. If you look due north, the elevation of the north celestial pole above your horizon is equal to your latitude on the Earth. The angle between this point on the celestial sphere and the star is 90 degrees minus the declination of the star. The right ascension of the star can be found by knowing the Local Sidereal Time and waiting for the star to pass across the north-south line that passes through your zenith, called the local meridian. If it takes the star 5 hours and 32 minutes to 'transit' your meridian, the Local Sidereal Time at that instant equals the right ascension of the star. You can find out what your Local Sidereal Time is by going to the US Naval Observatory and doing a simple calculation to convert from LST at the USNO to your location by computing the difference in the longitude. Sorry to be so sketchy about this.