It's worthwhile to point out that in Latin America, Christmas is not considered to be celebrated on the day of December 25, but rather the night of December 24 or "noche buena" (literally, "good night"). It's a subtle difference but important nonetheless.
The novena contains a series of prayers recited every evening. They include daily prayers to the Virgin Mary, St. Joseph, and the Christ Child, a series of poems of praise called the "gozos" that can be either recited or sung, along with a separate prayer specific to each day of the novena called the "consideración" that highlights an aspect of Mary and Joseph's journey to Bethlehem and the events that surrounded the birth of Jesus.
There is what you could call a quaint Catholic spirituality around these prayers. Many of the thoughts around using Christ's humility as a model for our own lives are worthwhile to contemplate. Occasionally, though, the reflections border on an absurdity particular to old-style Catholicism, such as in the prayer on the eighth day recounting how Mary and Joseph could not find a place to stay in Bethlehem: "The sound of each door that closed on them was a sweet melody for their ears." ("El ruido de cada puerta que se cerraba ante ellos era una dulce melodía para sus oídos.") Also, the prayer to St. Joseph can cause some chuckles because he is referred to as the "padre putativo de Jesús" (adoptive father of Jesus), where "putativo" sounds too close to a Spanish curse word. Nowadays the offending word is often replaced by "adoptivo."
Following the novena, the family will often sing traditional Spanish Christmas carols or "villancicos," either playing the instruments themselves or singing along to a CD. In some cases the novena becomes a social event for inviting extended family members, with food and drink served after the prayers are recited.