You can sign up with your QQ ID and QQ password directly.
More on WeChat:
- Delete only a message or the history of conversation on WeChat (Android, Blackberry, iphone, Symbian Samsung)
- Can I copy a picture and paste it in another conversation or chat on WeChat?
- Can I copy a text message on WeChat?
- Can I forward a voice message on WeChat? (Iphone iOS)
- How can I forward a text message on WeChat? (Iphone iOS)