Im a newbie so please be gentle!

I have created a website using layers and the main pane is scrollable but hidden (I hate ugly scrollbars). I want the pane to scroll down or up when you click the gif up or down arrow I have created on another layer - how do I make these buttons perform thata ction? I.e. 'on click, scroll layer X up' and 'on click, scroll layer X down'? I have no idea what to do!

Many thanks in advance