Start with education. Check out the Wicca forum if you are interested in that path. Read some books and articles on the subject. There are several articles on here worth the read and some of the posts will answer your questions.
Try to figure out if you want to just be a witch, Pagan, or a branch of Wicca. Don't feel like you have to follow any specific branch or path or anything. Just do whatever spiritually enlightens you. There's lots of paths out there, and I would suggest doing some research. You might want to look up things like...
Secular Witchcraft
Wicca
NeoWicca
Alexandrian Wicca
Dianic Wicca
Gardnerian Wicca
Druidry
Kemetic Pantheon
Hellenic Pantheon
Asartru
Or Celtic Paganism (not sure what the official name is)
Alexandrian and Gardnerian Wicca are more secretive, so they won't disclose much about their practice. Most I could find were a few small differences. They won't reveal anything that happens during a ritual or the names of their God and Goddess unless you're a part of their coven (which is a requirement in those types of practice.)
Dianic Wicca worships the Goddess Diana, of course. I don't know very much about it except that it has been called the more "feminist" form of Wicca. It puts a lot of emphasis in the Goddess.
NeoWicca has been called the "New Age" "fluffy bunny" Wicca, but I like it because I like to call myself a fluffy bunny type person. Some people claim that NeoWicca is a fraud type of Wicca. That's really up to you. It's more loosely set and practical. It is less strict and common among solitary practitioners. I can't speak for everyone on this, however. Wicca is a very diverse path.
Druidry is a form of nature worship. I believe (I could totally be wrong) that it came from the Celts or some similar group...? I have heard that you also have to be a part of a Druid community, because Druidry is more community-based. (Some Druid please tell me if this is right.)
Kemetic Pantheon is Ancient Egyption mythology. (Awesome)
Hellenic Pantheon is Greek Mythology. (Also awesome)
Asartru is the resurrected version of Norse mythology. (Also really cool.)
The Celts had their own Gods and Goddesses as well.
(Those last four are just different types of polytheism.)
Heck, you could be a witch and worship Satan if you want.
Or you could be a modern Satanist and just worship yourself.
Some witches just do witchcraft, and don't worship anybody. (Secular witchcraft)
Witchcraft is just a skill, and anybody can learn it. It just takes practice and research.
Finally, don't take my word for anything. I don't claim to be all-knowing, and if any of this information is wrong, I apologize and let me know so I can correct it. I'm just trying to help you out. I would suggest looking up the paths that interest you and talking to some real practitioners. Blessed be :)
