Promoting a teespring campaign, and I need help.

Does anyone know any low cost means of promoting a shirt? it's about coffee, and i have been promoting it to females 21-45 on facebook. and coffee fans in many other places, but its not working. I already put money in to promotion, but i'm not doing it right.

Whats the shirt look like?

I think you have to go in depth for targeting. Btw are you showing ads for post engagement or click ? How much spend so far? My friend made his first sell after wasting $500 and now he drives a $50 K car. Dont be demotivated.
Try to read/watch more tutorials.