It is easy to set how you want to activate thumbnails on your product gallery with the Woo Gallery Slider Pro plugin. Follow the steps below:

(1) From your WordPress Dashboard Menu, navigate to WooGallery Slider > General. 

(2) Under the General settings tab, you will find the Thumbnails Activate On option. Select any of the options:

• Click: The user or visitor has to click on the thumbnail to change the product image.
• Mouseover: The product image will be replaced when the mouse hovers over the thumbnail.

(3) Click on Save Settings and refresh the product gallery to see the changes.