Creating new reference:

To achieve this you need to go to the shop-locator.js file. There you will find displayMarkers function. You will need to add there an extra reference for the .json file

Just like you can see on this image below:

Now you can add different marker for each place you want to show on your map.

Adding markers:

Just go to the .json file where you are keeping all the json marker and add new field with the path to the image you want to use:

Please remember: All of the locations in the .json file need to have icon field with the path to the image.