1. Beauty and the Beast Despite there being years and years of pre-existing exotic vampire folklore from all over the world, it really has only dwindled down to two types that actually sell in this day and age. Either: A) Smoking hot undead vampires that want to sex you or B) Incredibly violent gore-loving animals that want to kill everything.
How does one come down to choosing?
Well, just try and figure out what kind of audience you're going to pander to. The main ingredients are sex and gore at the heart of this thing. Forget all the mystery, intellect, gothic nature, and deeper themes works such as Dracula had. It's the 21st century, we only have room for sex and gore here, people.
Two modes. That is it.
The modern reader can't handle anything else.
2. Dining Habits It doesn't matter how hot, lady-like, gentleman-like, or whatever-like your vampire is. Every time she or he eats/drinks, it must be either incredibly messy or they must drip it all over their shirts, the tablecloth, you, furniture, everything else, etc. That is something that simply never changes. Even a 500-year-old stately creature from somewhere in the ancient depths of Europe must find himself reverting to the eating habits of a two-month-old baby.
Is it for scariness? Mysteriousness? Gross-out factor?
Just that almost every vampire does it for some reason and so should yours.
3. Male Vampires Vs. Female Vampires Male vampires are usually the angsty ones and constantly lament over the state of their undead-ness while the female vampires are slutty and seductive and do a lot less lamenting and a lot more sexing-up.
...what did you expect? The horror genre isn't a place for women, silly. Even undead ones. Why do you always think they're getting hacked up or stalked or forgetting to charge their cell phones as the creepy man outside the abandoned house watches them?
4. The Opposition There must always be a secret organization and/or hunter to challenge your vampire. Either a human organization
5. Somewhere Out There There is a Nazi-version of your vampire. No exceptions. Because Nazi vampires are more common than any other "soldier" vampire. Also, more than any other, other kind of vampire. Napoleonic, Civil War, anything pre-dating 1930 or 40-something, GTFO.
Even if they're not "canon" to the story, HELL, or even in the same -time period-, who cares. Killing a strange variation of zombie wearing a badass uniform usually just does it for people.
6. Sound of Death Every vampire must hiss and/or screech, even at the risk of ruining the "scary" effect and making them look like third-graders pretending to be either cats or exotic birds in the process. Every vampire needs a sound.
...it's just that these "sounds" usually consist of the same. Damn. Thing. in almost every fucking
piece of available vampire media.
Besides, what the hell else are you supposed to do? Make them squeak or something?
7. Setting Vampires these days either have a thing for "castles" or ancient-like dwellings, or public high schools. Pick one. Sometimes they'll frequent antique bookshops, cemeteries, freaky pawn shops, or the anime section of Hot Topic, but mostly it's just castles and high schools.
8. Shock Value The more your work has of this, the better it will be and/or stand out. In fact, it is secretly every vampire author's job to outdo another in levels of shock value in the work. Sometimes it also helps to get borderline Satanic. Actually, it's better to just be Satanic. Fuck Victorian themes, fuck subliminated (in this day and age, yeah, sure) eroticism, fuck your allegories and themes, fuck your diverse ancient folklore.
Just shove it down to sex, violence, occasionally desecrating sacred objects, and shock value.
OR if you're feeling extra-hardcore, just take all that out as well and leave nothing but a shell of the original monster and make something nice-and-romantic-and-lovey-dovey and fluffy.
Actually, go crazy. Paint the walls. Sparkles? Sure. Why the fuck not? Hey, why not just dip it in chocolate, set it on fire, and call it "Dracula." Fuck, make them gingerbread shaped. Glue several unicorn horns to that fucker. Dip them in cheese, make them turn into hamsters. Make them eat starch and have them live on cereal boxes and give them awesome names like "Count Douche-ula."
Whatever. Just...there is no hope for you people.
Other than that, hope you enjoyed this installment of "How To".
Thank you and good night.