For starters, the first thing that I had to do to adjust to the Spanish lifestyle was to throw my entire time schedule out the window. Spaniards operate on a much later schedule than we do in America. Everything is much later here, about 2-3 hours later. Generally, people will wake up around 9 or 10am and eat a very light breakfast consisting of a small piece of toast or fruit sometime before noon. They are then good to go until lunch which is around 2:30pm and also the biggest meal of the day. Dinner is then generally not served until around 10:00pm at night. To tide them over between this large gap between meals, Spaniards will generally go out for tapas or little snacks and a drink at some point in the early evening. Luckily, our host mom, Mar, had a little mercy on us Americans and serves us dinner at 8:30pm by which time we are all more than ready for our "early" dinner.
The next notable difference would probably be the street life. The streets are the most active that I have ever seen at almost all hours of the day. This is because people walk everywhere or take the public transportation via the underground metro. Very few Spaniards brave the traffic with cars and the ones that do are more often than not yielding to the constant flow of the pedestrians. The pedestrians themselves are super hard to navigate, because there are no rules such as stay on the right side. I have learned that you have to assert yourself and just plow through like the rest of the Spaniards or you'll be Dipping, Ducking, Diving, and Dodging forever and never get to where you need to go. The streets are least active early in the morning (early being any time before 10am) and during siesta which is between like 2:00pm and 4:00/5:00pm when literally almost everything closes for this little nap hour.
The lone metro rider, a very rare sight! - only because it was the last stop before it closed.
Now this idea of a siesta leads me right into my next key note difference which is the idea of when exactly the typical Spaniard actually works. If I were to go based on what I've seen, I would say the answer to that is never. There are a few explanations for this including the fact that Spain does have one of the highest unemployment rates in the European Union and one of the least amount of work-week hours in the world. They take work a lot less seriously than we do in America, as my host grandma Tata puts it, "you live to work and we work to live."
The last truly notable difference that I have come across is the home life. Families are super close and eat every meal together barring school/work schedules. When they greet one another or say goodbye or even sometimes if they just leave the room, they give each other "dos besos" (two kisses) one on each cheek. Also, it is very uncommon for kids to move out before they are married, even in college most Spaniards live at home. The grandparents almost always live with one of their kids rather than in their own home or a nursing home. Kids here don't really have friends over or play dates like they do in the U.S., the homes are mostly just for family unless a scheduled, more formal invitation is extended.
While just a general overview, these are the main differences that I have observed thus far and I'm sure as I get to know more of Spain, I'll learn some more details that separate the States from España and until I return I will be embracing them all to the fullest!