I am creating a twitter application in iphone using oauth. But my application request for:

```
oauth_consumer_key,
oauth_signature_method,
oauth_signature,
oauth_timestamp,
oauth_nonce,
oauth_version,
oauth_callback,

```

Please anyone help me how to create all these keys for my application.
In my twitter account xauth is disabled by default. So, how can I enable it in my application?