The background needs to be simple and contrast strongly with the subject. This way, to win you must not only have the right pictures on your tabla, but you must also figure out the poem or riddle. I could see classes making up poems and riddles suitable for their age cohort. Individual game cards typically have 16 pictures which are brightly colored and have the Spanish vocabulary naming the subject written at the bottom. Someone has mentioned there are phrases or poems attached to the subjects.
Participants can play with more than one card at a time.
The caller draws Loteria picture cards from the deck one at a time and calls out the name of whatever is pictured on the card. Participants mark any matching pictures with something like a dried bean. Players are trying to mark four pictures in a vertical, horizontal, or diagonal row, or mark the four corners in order to win. There are several different ways that players announce a win. The caller sometimes includes the traditional phrases or poems associated with the individual pictures that are drawn.