Landing a decent right hook can be a finisher in a fight. To connect this properly with as much force as possible, you need to make sure you body is lined up correctly , with all your weight pinpointed at the point of contact. From your guard position (based on Orthodox stance) slightly drop your right hand and circle it forward towards your opponents head (temple or jaw). Keep your forearm, elbow and fist as horizontal as you can (this can depend on the height of your opponent). As you turn your hips with the punch, twist your back leg, rotating on the ball of your foot and pushing up from the floor to add extra power.
In the video, I show 2 basic examples of the hook. The long hook and the short hook. The long hook is obviously a longer range technique that can be thrown in a combination or as I show in the video a counter from the jab. The short hook, is for when you are up close and personal . I hold my fist with the knuckles aligned vertically. This is my own preference, I feel it can produce more power in my punch when I do this. Feel free to experiment with knuckles held in the vertical or horizontal position to find which best suits you .
If you can, when you practice on the bag or on the pads, try and use the slip and hook technique as well, rather than adding the hook at the end of a combination.