My favorite cafe in New Orleans is Hey! Cafe, where they offer nitrogen-infused cold-brew coffee. It's frothy like a good beer and the little nitrogen bubbles feel so nice in your mouth... it's just the best. I like to call it "Nitro-brew."
When I was oozing over how amazing this coffee is one day, I snapped a photo on my phone and used this as the background for my lettering.
I had to mess with the color range (select > color range) to select and remove the background. I made the lettering white by merging each separate lettering layer with an inversion layer. I duplicated the background layer 5 times so I could merge those with my 5 lettering layers. That way, each of my layers contained the coffee image with the lettering. Then, I put them into the timeline for my animation.