The best type of avocado to use is the small Hass variety. It has a lot of flavor and a creamy consistency that makes it perfect for guacamole. Florida avocados are larger but they contain more water so they're not as good for guacamole. Choose avocados that are firm but still have a little give when you push into them with a finger. If you're not planning to make the guacamole for a day or two, plan ahead and choose firmer avocados.