1. Experience It's often said that there is no better teacher than experience. This is true especially when it comes to fighting. You can have the best home gym, train at the most expensive camps, and workout all you want but it doesn't come close to having a good sparring partner and mitts person. You really want to be training around people who can kick your ass and teach you why you're getting your ass kicked. You want to have the experience of actually going toe to toe with other people than can fight. Hours on the heavy bag, running for miles, and doing stuff you see in the Rocky movies helps but when it comes to combat sports it's all about the experience points. The greatest fighters of all time like Mike Tyson, BJ Penn, Floyd Mayweather, these dudes are renowned for their work ethic while sparring or practicing. 2. Cardio Next to learning how to fight by fighting, cardio is how you fight longer than the other person. Swinging punches is an easy way to gas yourself out. It's almost like running is easier, if you've ever gone rounds with then people you know. Running long distances, sprints, cardio-kickboxing. These are all solid ways to make sure that if you ever do compete or need to defend yourself, that you can go the distance and remain full of energy while your opponent is gasping for air. Fighters with great cardio who you see never setting the pace and never losing tempo are Khabib Nurmagomedov, Jon Jones, Urijah Faber. These dudes are well known for relentlessly chasing down their opponents and never ceasing making it rain punches/kicks because their conditioning is that serious. 3. Footwork Footwork is super important. It borderline is already picked up with #1 as experience but, footwork deserves it's own niched training outside of sparring or mitts. Agility drills, learning to hit a target regardless of where you step, learning how to pivot and throw your weight in with punches is something that the best display well. Footwork is your base for fighting, your balance, how you set everything up. If you ever want to study good footwork watch Anderson Silva, GSP, and especially Dominick Cruz fight. Dominick Cruz actually has a free footwork program you can find, it's great. 4. Power POWER. When you see people like Francis Ngannou, Kimbo Slice, Brock Lesnar, Dan Henderson, get in there and stone cold slobber knock dudes out in one punch. That's power. It takes not just raw strength but the technique to utilize it. You'll see lots of big strong dudes kind of tense up as they swing, but that limits your power. Physics lesson, force equals mass times acceleration. So the mass of your fist and body behind it, multiplied by how fast it's moving equals its force upon contact. If you pay attention to the bodies entire range of motion, watch Mike Tyson throw one of his famous uppercuts. That uppercut damn near comes from the ground up, he throws his legs, hips, core, and torso into the punch a full body range of motion and effort into one punch. Getting an uppercut, hook, or overhand from a heavy hitter that knows how to utilize their power is absolutely devastating. 5. Focus Fighters like Lyoto Machida, Anderson Silva, Jon Jones - meditate. There's something about being able to clear your mind and focus, that translates well into being able to control a fight or turn around losing one. Even the legends of combat like Miyamoto Musashi as the most influential samurai ever, Sun Tzu author for The Art of War, and many other famous warriors/tacticians from history liked their peace time to think and plan. Focus is an important part of combat as it's easy to lose your head and start scrambling. Remaining stoic, keeping calm, and approaching a fight with the energy as Anderson Silva against Forrest Griffin. That's really the kind of focus you want to have in a fight and you can work on honing it outside before the fight.