how to change the header part in a theme?
 

I have currently installed a theme in my forum, but i dint like the header look. I want to change the header part alone. what are the fields that needs to be edited to change the header?

just the logo or like more then just that? the header is usually in the header or navbar template. the logo you can usually change in the all style options

What hellbomb said. However, it'd be easier for people to answer/assist you if you could paste the header template content. That is, if you'd like a more precise answer to your question.