Do you mean here on Yedda?
If so, you cannot. Your question will show up and be associated with whatever screen name you are using. You can change your screen name, but then that change will be reflected in any/all other threads in which you have appeared.
At this point, the only way for you to post anonymously is to open a second Yedda account and choose an anonymous screen name to be used with that account.
Please note that while many before you have chosen to do such a thing for privacy reasons, there are other Yedda members who choose to do so for nefarious reasons. Therefore, do not be surprised if your anonymity results in disbelief and/or mistrust.
