Improve Your Fighting Skills

There are no steps to learning how to be a better fighter. With each person comes his/her own style of fighting. However, there are some tips.

Steps

Always keep your knees bent. This will enable you to move quickly and easily in any direction.
Always keep your guard. Hands up to your cheeks or temples with elbows tucked into your sides. To block hook body shots drop your elbows. To block hook head shots reach your hand to touch the ear then to the back of your neck. Once you understand the block do it all in one motion.
Know how to dodge. Dodging is always less damaging to yourself than blocking, it also allows easier access to attacking straight after your opponents attack.
Judge your distance. If they are quite far away expect kicks. If they are arms length away expect punches. If they are quite close expect elbows and knees and grappling.
Try not to go to the ground in a fight. Unless you are experienced in ground fighting (e.g jujitsu, Brazilian jujitsu, judo etc.) But even then remember that there are no rules on the street. Stomping, biting, gouging are all acceptable and are especially dangerous on the ground.

Remember to be aware of your surroundings and try not to get cornered.
Let your opponent come to you. You don't have to be the one that has to throw the first punch.

Expect to get hit. Even professionals and experts have been hit before. Try to block as much as possible but if you know you cannot block, try to reduce the amount of force being applied. For example if being hooked to the right of your head, move your head left as you get hit to reduce the impact.
Remember that learning a martial arts from a martial arts gym or dojo is much more effective than learning via videos or reading text.
Remember that movies are choreography and are filmed with the intent of entertaining the audience. Try not to copy movies and instead join a martial arts gym or watch proper tutorials.
Running is cowardice. But retreat is a tactic. Know when retreat is the best option, and live to fight another day. Sometimes its just not worth it.
Always use reasonable force. If you are being mugged, only subdue your foe. If you are sparring, use light force. Only use full force when life is being threatened or in a professional fight.