First pic looks like a wake for this guy..
It's actually art from Jose Guadalupe Posadas, he was an engraver and illustrator.
This piece in particular is know as "La Catrina" which is a female version of 'El Catrín" which is a term used in Mexico that refers to "Dandy" people.
It was very common in the early 1900's.
He created a lot of amazing "Day of the Dead" art.
I know almost nothing about the day of the dead. How does one celebrate it properly? 'Cause it sounds like something I'd really dig.
Well,
there's different customary things depending on the region of Mexico or Central/South America.
But basically in Mexico, people build altars or shrines at home in remembrance of a deceased family members. Usually with his/hers favorite items and food, as well as some pictures and lots of Mary-gold flowers, candles and Copal (pre-columbian incense). As well as Tequila, Pulque and Atole (corn drink)
Sugar skulls and "Pan de Muerto" (Bread of the Death) are food and/or decoration people use.
A lot of people go to cemeteries and decorate the deceased's grave, with the altar. Tell stories about them, write poems (called "Calaveras"), play music, sing and dance.
It is believed that the souls of the deceased will com back to enjoy the food and drinks left for them in the altar.
Lately some people dress-up with mexican-themed costumes.
This celebration has it's roots with Pre-Columbian cultures in Mexico, and lasted for weeks, I believe...
It's now combined with some Catholic rituals.