DiagorasRadix
Person
Once you are a vampire, it is too late for a simple cure disease potion to work. That only works in the first three days you had the initial infection, during which you received multiple warnings that should have suggested something was up. In order to cure full-blown vampirism, you need to begin the quest to cure it, or become a werewolf. Being a vampire can be a little bit of a hassle and chore, but it really isn't all that bad if you pay attention, and can be useful early on as an assassin or thief before your sneak or illusion skills have grown. If you are a Dunmer you don't even go into the negatives in terms of elemental resistances until stage three (which you should rarely even slip into). You just need to get the Lady stone in order to continue regenerating health and stamina in the daytime (magicka still won't regenerate until night, or indoors), and stay at level one vampirism as much as possible if you plan on being out in the day. Just bring a follower, order them to sleep in a bed, and feed on them while sneaking, easy-peasy. If you still want to cure it, here you go:
http://elderscrolls.wikia.com/wiki/Vampirism_(Skyrim)#Curing_Vampirism
http://elderscrolls.wikia.com/wiki/Vampirism_(Skyrim)#Curing_Vampirism