It's all about the flaws! The right flaws can make any character a treat to read. Think of a big block of pure marble - it's bloody boring, until you add some nicks in it and create a statue. I know, my depth is illuminating. But seriously, flaws really make a character.

I will use my character as an example:

- He's pretentious, but he's a complete tool outside his own element. Also, he can't hold on to one thought at a time without drifting into inane ideas. For this reason, he may go on about the duties of a gentleman -blah blah blah - but he'll also freeze up when you ask him to transfigure something or talk about a famous composer. Just because you want someone to like you, doesn't mean you should be pro-star at everything they're talking about. If your proficient in or have absolute knowledge of everything brought up in dialogue, then I expect to see the freakin' Batman as your RP character (lest I'll call bull-poopie).

NOTE: I'm basing this on a lot of fantasy novels in which the characters may not be of the -Sue variety, but are equally deus ex machina.

- Appearance: He's not fantastic looking, just strangely effeminate. He's lanky, and pale (sigh - everyone in fantasy wants pale skin, but then I walk around in shorts and suddenly it's "Either those are leggings, or you need a tan"). His eyes don't 'sparkle mischievously' nor are they any exotic shade: they are eyes and they are often a dull and unfocused grey. It's how he presents himself that really matters.

- His family: I soon realized everyone was pureblood and rich, so my character's family is one that's slowly going broke. As a result, status is all Chaucer can really flaunt, so the option to be able to buy whatever he wants is out the window. It's important not to consistently grieve over one's flaws because that is irritating and means you're attention-starved as an RPer. Neville Longbottom is a good example of how a family flaw should be treated - bring it up as it suits in posts, but do not focus on it.

- Looks SHOULD come last, but I'm a hypocrite. All my best characters had personalities first, not detailed ones but enough to get a good grasp of the kind of person they would be. Too often I give in to the lure of drawing the character first... they are always so comparatively bland.

That's about all. I would recommend for beginners to take a few (no more than three, preferrably one) core personalities from other characters you like (from wherever) and build up from there. Let's say I like a character called BOBBY-BOO from some random novel who has a number of traits that I fancy. I'll take his trait of being really superstitious and work different traits around that one.

Long-winded, but character design is a hobby for me.