image headers on child forums

[lynx31]

Hi,

I'm currently using a VBulletin demo ahead of taking out a package. What I want to do is insert a jpeg picture at the top of each individual child forum I have created (one per child forum). For example if I was doing it on here it'd be going to the "vBulletin Pre-Sales Questions" child forum, then entering the jpeg in the space between the User CP bar and the 'Threads In Forum' bar - i.e. the gap on this forum where I can see the following:

You are currently showing up as unlicensed. To download mods and/or participate in our community. You will need to prove that you have a valid vBulletin license. To do this, go to vBulletin.com Member Support. Upon entering the support area, enter and/or verify your "Contact Email Address". For further information, please read our "Showing Up As Unlicensed?". vBulletin Pre-Sales Questions: Use this forum to ask questions prior to purchasing vBulletin, regarding existing hacks and whatnot!

I'm new to this so don't know how, from the admin menus, to insert a relevant HTML / image / text box such as the above

any step-by-step instructions appreciated!

many thanks