If you want to hook your readers, you’ll need a character that leaps off the page. A good character is believable and interesting. Firstly, be careful your character is not of music-hall-cliche stock (dumb blonde, greedy banker, uber-organized German, upper class twit etc…) – the problem here is that the reader will have met your character far too many times before to find them interesting now. As usual, turning the cliche on its head can be a good place to start getting ideas (chess-master page three girl, a banker who secretly gives away money etc…)
Also, don’t focus on describing what they look like from head to toe. In fact, their general physical appearance is not so revealing – the key is often in the interesting quirks and blemishes. Moreover, you ought to climb inside your character’s skin, get to know them intimately and let the reader see how they tick. It is good if there is something unusual about them. Here’s a sample list of questions you could mull in order to give your character depth:
Rather than describe the colour of their hair and eyes, write instead about their height.
What about their gait, posture and walk? Does he flutter, jerk, flap or glide?
If you first met this character, what would strike you most?
Does s/he resemble an animal?
What is their natural scent?
What sort of diet do they have and what has been the physical impact of this regime?
What does their best friend think of them?
What happens when your character gets drunk?
What does your character have in his/her pockets/handbag/beside table?
What is your character’s favourite joke?
Also, to make your character particularly memorable, give him/her/it a singular physical attribute your reader will long associate with them. Think of it this way, if you were going to a costume party dressed as Harry Potter, Sherlock Holmes, Miss Havisham or Liesbeth Salander – what would you need? My guesses are, respectively: a lightening bolt scar, a deerhunter hat and pipe, an old wedding dress, and a dragon tattoo. Try to imagine what you’d need to be recognizable as your character.