Make a testimonial image clickable button

[jasongoosen]

Hi,

I want to make my testimonial image clickable, I tried editing code to what i found but doesnt seem to work.

Once this image is click I like a pop up window with additional information.

Modal popup is an option but not getting to work on my theme. (Maker theme)

example pop up attached.

Could someone help me with this issue?

Very grateful for your help! 

Thank you in advance Jason.