usually nothing big happens. in fact parades aren't common at all. I didn't know they did one in mexico city even :u do they? I thought that's something that they made up for that 007 movie. Usually people stay home, if they feel like it, make an altar to their lost ones someplace in their home, if not, you literally do nothing. Some places do like altar contests on parks n stuff, that's nice. There's also markets where you go buy the traditional stuff for the holiday which are great cuz you can buy shittons of sweets. Bakeries do the traditional bread for the holiday which actually tastes great and you only get it in this season. Some people have the day off, like students and banks and gov. institutions cuz they're lazy fucks, but everybody else works as usual. That's pretty much it.