I had a couple minutes after class this Saturday before I had to head home to help my wife around the house, so I recorded an ugly, quick-and-dirty demo of a broken-down bunkai drill I like for the beginning of Naihanchi Shodan. I would have preferred better angles, close-ups of some parts, more detailed demonstrations, better lighting, etc., but I did what I could with the time I had. I really appreciate Brent, one of our intermediate teen students, for letting me beat up on him :P. As always, there are many applications that could work for any given movement, so these are not the only applications we use for Naihanchi and they certainly aren't the only ones out there! I'll also give the disclaimer that I am not a representative of my dojo, organization, or style--this is just some of the stuff that I work.
The scenario starts with someone grabbing you and threatening you. The first movements of the kata are used a pre-emptive strike in this drill, where you grab your attacker's head and strike it--in the demonstration, I simply punch the face, but you could backfist the nose or use small-surface strikes like ippon-ken on kyusho targets. From there, I lever the head down into a knee strike, and shovel kick the attacker's knee.
The second part of the drill is when you have failed to pre-empt your attacker and they let go of you with one hand to start punching. You deflect and trap the punch beneath your arm and use that hand to slap the back of their head while elbowing them in the face. Just like the first technique, the strike (elbow, in this case) can be thrown as many times as necessary, although I only did it once in the demo.
The third part of the drill is when you have done one of the first two (I only demonstrate this off of the second part of the drill in the video, though) and your attacker blocks and clinches with you to prevent you from hitting them more. From there, you grapple with your opponent (normally I like doing this randori-style, plus strikes) until they try to make space to start hitting you again, at which point you drag their pushing arm across your body into hiji osae gatame (elbow press lock). That lock can be used to control the attacker, dislocate the joint, or simply bring their head level down, and then you can follow up with hammerfists or punches to the head/neck.
This drill can be worked into just about any self defense drill, because often when people start getting hit and don't like it, but also don't want to quit fighting, they will grab onto you and start wrestling with you. From that same situation, I have other drills from Naihanchi, but this was the only one I had time to record. I hope it is clear enough for you guys to see where I'm going with it, though! Eventually, I would like to record other applications that can be used for a variety of other scenarios.