It is composed of dark green wood and bamboo poles that hold together a white sign that reads "lemonad" in red writing, with the letters L and M being capital and the rest being lowercase.
Role in episode
Patrick originally sells normal lemonade at this stand, until he finds out that he can make lemonade out of Squidward's ink. During the episode, Patrick finds ways to scare Squidward so he can spurt out ink lemonade for Patrick to sell at his black lemonade stand.
Near the end of the episode, when Squidward finds out Patrick is scaring him to sell his ink, Squidward destroys Patrick's stand and makes a new stand so he can sell black lemonade to people straight from the source.