Set a metronome to run at any BPM. BPM stands for beats per minute and determines how fast or how slow a beat is occurring.
Practice counting four beats. A metronome will click every beat consistently until you turn it off. Practice counting a whole count, which consists of four beats by saying "one, two, three, four," one number for every click.
Count every other beat. Half notes consist of a note being played twice for every four beats. Strike the drum on the first beat and the third beat or on the second and fourth. Half beats get their name from cutting a whole 4-beat count in half.