This guide explains how to create a long image to use as the source for the scrolling area in a demo. We will use Paint in this guide. If you have a Mac, you can use Preview to achieve this task - the process is similar.
Merging images with Paint
1 Open all images in Paint.
2 Cut the unnecessary parts from all the images (for example the upper and lower bars). First, cut the upper part: select the entire image (Ctrl+A) and drag it upwards. Second, cut the lower part: drag the bottom image handle upwards (not the selection handle).
3 In the first image, make enough space for the other images, which will be pasted here. To do this, drag the image handles.
4 Paste all other images in the first one, one by one, and adjust their position.
5 Done! Save the long image and use it as a source for the scrolling area.
You find a more detailed guide here.