Psh, who likes Tom Hiddleston anyway? *eyes Tumblr apprehensively*
As I know you all have been waiting for this post with such excitement that you haven't left your room in weeks, drawn all your blinds, and lived in a temporary state of eternal darkness, I come bringing the Loki you've been wanting. *smiles at Tumblr*
Look, I made a guide!
tricks to strong characters
trick #1: introduce your character's vital strength when you introduce your character
Whatever your character's important strength or talent that gets them through the story's climax, tell the reader within the first scene they meet your character. Hermione, for instance, shows off her magical knowledge when she first meets Harry and Ron on the Hogwarts Express. Katniss goes hunting in the first chapter. Clary draws/paints in the first chapter.
trick #2: think of this first scene as your reader speed dating your character
The reader wants to know about this character. What they're like. What they want. That first impression is going to stick.
But be coy. Don't tell the reader so much that they're not interested in a second date.
trick #3: define your character in their first scene
How do you want the readers to see this character? Do you want them to fall in love with them? What about their character is romantically appealing? Do you want them to hate them?
Don't go crazy. Your villain doesn't need to set a bag of adorable kittens on fire in chapter 1 for your readers to get the idea. In a way, even a seed of feeling is the best sort, as it can sprout and grow throughout the story until it becomes blind fury. Take Joffrey Baratheon, as an example.
trick #4: pick a strong element of your character that will change throughout the story
Give your character an attribute that will change with your story's progression as your character evolves. This depends on your story arc. If you want a character to start out unlikable but become sympathetic, make their unlikeable characteristics strong in the earliest scenes and lessen in the later ones, until they might disappear completely. Think of Sansa Stark, who grew less obsessed with her idyllic lady-like world and became stronger, cunning, and more than sympathetic.
trick #5: give them a quirk
This does not mean your character has to be quirky. They don't need to have a bow-tie obsession (even if bow-ties are cool). They don't need to have an inhuman knowledge of an unusual subject.
Quirks are simpler. Maybe they have a catch phrase. Or a favorite gesture. Maybe they make up ridiculous curses that makes them sound like a third-grader. Maybe it has something to do with their appearance, like a favorite bracelet or preference for overly baggy shirts.
But give them something. If you describe a character has having brown hair, blue eyes, and of average height and slightly above average appearance, you've just described around fifty percent of female YA characters. Give the reader something unique to hold on to. Not so unique you had to go scouring Wikipedia for unusual hobbies, but enough that the reader won't forget the character when you introduce them later.
Bonus Points: Make the quirk important in the main plot or a subplot.