To become a vampire in Skyrim is simple. Its been the same way since TES IIIorrowind. If you don't care that you grow a little more pale and your eyes are completely red then by all means continue reading.
All you need is a vampire, and a healing spell if you have low life or are a low level.
First off find a vampire hideout, in this guide we are going to use Broken Fang Cave.
Just west of Whiterun lies a cave named Broken Fang, Home to a few vampires.



Go inside, and let them attack you. With each hit that lands on you, you have a small chance to contract Vampirism. So let it hit you a few times till you contract Sanguinare Vampiris. After that leave the cave, Wait outside the cave 3 days and then take walk around a bit after that your screen should turn red giving you your newfound vampire powers.
Being a vampire takes responsibility, The more days you go without feeding on a human the more people around town will notice that a blood sucking monster has been walking around town and attack you. I believe after 4 days without feeding will cause Villagers/Gaurds to attack you. With each day that passes without feeding you become weaker to fire spells but you also get a few more neat powers.

Here are the effects you get from becoming a vampire:
  • Weakness to Sunlight - Health, Magicka, and Stamina do not recover while in sunlight and the skin will appear to slowly burn as the player spends time in the sunlight.
  • Resist Disease - Your vampiric blood gives you 100% resistance to disease.
  • Resist Poison - Your vampiric blood gives you 100% resistance to poison.
  • Night Stalker's Footsteps - Vampires are 25% harder to detect while sneaking.
  • Champion of the Night - Illusion spells cast by a vampire are 25% more powerful.

Now the Stages for when you go without feeding:
Stage one:
  • Resist Frost - Your vampiric blood gives you 25% resistance to frost.
  • Weakness to Fire - Your vampiric blood causes you to be 25% weaker to fire.
  • Weakness to Sunlight - Health, Magicka, and Stamina do not recover while in sunlight and are reduced by 15 points.
Powers to Stage one:
  • Vampire's Servant - Reanimate a weak dead body to fight for you for 60 seconds (can only be used once a day).
  • Vampire Sight - Improve night vision for 60 seconds (can be used multiple times a day and be toggled on/off).
  • Vampiric Drain - Absorb 2 points of health per second from target (novice destruction spell, cost of 5 magicka per second).

Stage Two:
  • Resist Frost - Your vampiric blood gives you 50% resistance to frost.
  • Weakness to Fire - Your vampiric blood makes you 50% weaker to fire.
  • Weakness to Sunlight - Health, Magicka, and Stamina do not recover while in sunlight and are reduced by 30 points.

Powers added to Stage Two:
  • Vampire Seduction - Creatures and people up to level 10 are calmed (cease to fight) for 30 seconds.
  • Vampiric Drain - Absorb 3 points of health per second from target (novice destruction spell, costs 10 magicka per second).

Stage Three:
  • Resist Frost - Your vampiric blood gives you 75% resistance to frost.
  • Weakness to Fire - Your vampiric blood makes you 75% weaker to fire
  • Weakness to Sunlight - Health, Magicka, and Stamina do not recover while in sunlight and are reduced by 45 points.
Powers added to Stage Three:

  • Vampiric Drain - Absorb 4 points of health per second from target. (Novice Destruction spell; costs 12 Magicka per second.)
Stage Four ( Try not to get to this stage. ) :
  • Resist Frost - Your vampiric blood gives you 100% resistance to frost.
  • Weakness to Fire - Your vampiric blood makes you 100% weaker to fire.
  • Weakness to Sunlight - Health, Magicka, and Stamina do not recover while in sunlight and are reduced by 60 points.

Powers added to Stage Four:
  • Vampiric Drain - Absorb 5 points of Health per second from target. (Novice Destruction spell; costs 15 Magicka per second.)
  • Embrace of Shadows - The vampire becomes invisible, with improved night-vision for 180 seconds (can only be used once per day, interacting with anything will remove invisibility as per usual).