With the help of a straight pin dipped into some fabric glue, put a dot of glue on the belt buckle with the head of the pin where you want the rhinestone to go. Make sure you use only that much glue that the rhinestone is able to cover up completely. You could use a cotton swab for the larger rhinestones. Pick up a single rhinestone making use of a pair of tweezers and force it down on the glue spot on the metal belt buckle. Try to hold it for a few seconds before you release it. Go on repeating the 3rd and 4th steps until you cover all of the space on the belt buckle which you designed earlier.