This is one way you can create a hero, villain, or sidekick. A freeware system I created, you can use it if you want; you can skip a step, do them in whatever order you please, or completely ignore it: knock yourself out.
Step 1: An idea
Think a general idea for your superhero/villain: it could be an alter ego, power, just anywhere you can start from, and build the hero around this core idea.
Step 2: Origins
How did your person become a hero/villain/sidekick? was she/he born with special powers? Did he/she get them in later life? Or is he/she simply a regular person who decided to do some good/evil?
Whether there are super powers or no, how did this person make the decision to be good or evil? What caused him/her to change?
Step 3: Alter ego
You can ignore this step if you want; not all superheroes/villains have an alter ego.
Your alter ego depends a great deal on how you became a superhero/villain: Superman was born irregular, so he had to make a new identity, but Pete Parker and Bruce Wayne were ordinary people who made new identities for themselves as Spiderman and Batman; the hero was, in a sense, their alter ego.
Whatever alter ego your person has, it should be one that permits them to go off on little notice to rescue/destroy the world.
Alternatively, you could put him/her in a situation where he/she has a great deal of trouble getting away to
Step 4: Livery
What are your superhero's/villain's symbols and colors? what does he/she use to represent her/himself? what inspires them? Elevates them? What strikes fear into the hearts of do-gooders/evildoers everywhere?
Your livery could be connected to your powers, like Spiderman, it could be connected to what motivated you to be a hero or villain in the first place.
Step 5: Powers:
Powers vs. no powers
A super hero/villain with a super power is generally referred to as a metahuman; 'meta' is a Greek word meaning 'after.' Hence, after-human; a superior example of the species, the next step in evolution, a genetically-altered
I firmly believe that all powers should come with a built-in weakness; Superman has Kryptonite, for instance, and Cyborg has to recharge his batteries
Some example powers, some with example (x) weaknesses
Telepathy x mental instability
Clairvoyance(being able to see things far away) x poor sight/blindness
Cairaudience(Being able to hear things far away) x poor hearing/deafness
Speak with particular type of animals(e.g. Dogs, birds) x speech impediment
Water breathing x asthma
Ultrafast/superspeed(being able to move faster than should be possible)
Prophecy(the ability to foresee the future) x blindness(a cliche, but a good one).
Microscopic vision(can see very tiny things)
Telescopic vision(can see things very far away)
Low-light vision x cannot see well in daylight.
Low hearing(the ability to hear subsonic vibrations)
High hearing(the ability to hear hypersonic vibrations)
Tail(furry, or sting-equipped)
Wings(usable, or not)
Magic is a complicated subject when you're talking about superheroes/ supervillains; as a general rule, I think you should have a person be fluent in one type of magic, over others: e.g. a person who specializes in battle magic is unlikely to be very good at ritual magic.
Like Magic, I think shape changing abilities should be limited to one particular area of shapechanging: e.g. one fellow can change his appearance like a chameleon to look like anyone he wants, while another person can make his arms become a lot bigger to hit people with
Step 6: Equipment
No matter their powers, almost without exception super heroes and villains make use of equipment; grappling hooks and rope, radios, telescopes, smoke bombs, jets and cars, these can all be vital to the survival and success of a super hero/villain.
When picking out equipment for your OC, carefully consider each piece: does it fit with your concept of the character? does it work with your character's power(s)? And always be careful not to overload him/her; it'd be kinda hard to fight crime while carrying a whole armory on your back!
Cyborgs: when your OC is a cyborg, the difference between a superpower and piece of equipment can become blurred.
Step 7: A name
When making superheroes/Villains, I think you should leave the naming until last, when you have all the information you'll need to come up with a fitting name; of course, you are perfectly free to do different.
A name could be about your character's goals, powers, his/her origins; it could be name that holds meaning only for them. Again, knock yourself out.
Step 8: Tagline/Catchphrase.
A tagline could be what you start each episode with; it could be what your hero says when introducing himself. For a tagline example, every episode of Superman starts with: "Look! Up in the sky! It's a bird!" "It's a plane!" "No! It's, it's-" SUPERMAN!
A catchphrase could be what your superhero/supervillain says to introduce him/herself, what he/she sayd when he/she springs into action. For instance, whenever Underdog arrives at the scene of the crime, he declare: "There's no need to fear! Underdog is here!" While whenever Darkwing Duck springs into action, he looks grimly into the camera, and says: "Let's get dangerous!"
You don't have to give your hero/villain a tagline or catchphrase, but it really helps to set the tone of your character's adventures, and will help introduce him/her to people reading it for the first time.
Step 9: Friends.
A boon companion like Alfred, a sidekick like Robin, a contact like Commissioner Gordon, your hero/villain needs friends, allies, people to help him/her save/conquer the city/country/world/universe.
Step 10: Place.
A fortress of solitude, an underground bunker, apartment, farmhouse, secret lab, space station, extra-dimensional palace; your character needs a home base, a place to go to hide from their enemies, store equipment, and prepare for whatever heroic deeds/dastardly schemes are being cooked up.
Step 11: Setting.
Time, place, situation; are there Zombies taking over the world? Is there magic? Are you on another planet? These are all things that need to be worked out.
Step 12: Enemies.
Who are the bad/good guys? who is the cowardly villain/brainless tool of the corporate empire who dogs your character's every move, who attempts to thwart their schemes, to utterly crush him/her?