It’s frustrating when you start getting messages on Facebook from people you don’t want to talk to. A groovy feature lets you appear offline to specific friends, or appear online to friends you want to chat with.
Log in to your Facebook account and click on the name of the person you want to appear offline to.
Then click the gear icon to expand Options and select Appear Offline to Person for that user.
You can even add multiple contacts. To do so, click on the Options button under the Friends list bar and select Advanced Settings.
Select All Friends See You Except. Then start adding the names of the people you want to appear offline to.
If you just want to appear online to certain people, select the second option that says Only Some Friends See You and start adding the names of the people you want to appear online to.