Image scroller

I’ve searched all the Adding thumbnail posts on here and cant see this civered any where.

I’ve worked through the Adding Thumbnails tutorial on here and now trying to modify it. (

What i want to do is instead of it scroling when u move over the left or right is only have it scroll when you click a button on the left or right.

Also only want it to move one thumbail across on each click

Any ideas or links to posts much appreciated and sorry for posting another question on this much widely covered subject.