Two important books existed until the modern age that pertain to the ancient Maya people and their beliefs. These include the Popol Vuh and the Chilam Balam. They came from the highland and lowland sections of Mayan society respectively. The latter is made up of multiple books that describe how things were for various groups of people living in slightly different geographic locations. Inside lies the creation myths for these group of Maya, as they were around 1500 CE when they were already influenced by Spaniards coming over to share their own religious ideas.
To put it simply, the Mayan creation myth includes the planting of a huge tree of life by Huracán, the wind and sky god. The tree grew, spread out, and formed Xibalba by the roots, their version of heaven in the upper branches, and the Earth around the trunk. Animals and plants came first, and then the people were made to glorify the gods. Similarities between this and the Christian creation myth the Europeans brought over with them seem obvious.
The people themselves came about in various ways, too. First, gods made people from mud, but they had no mental power, intelligence, or will. They also couldn't move on their own, so the gods decided they had to do better. The next people were made from wood or reeds, depending on their sex. They moved, grew, and thought, but they didn't worship the gods. Also, they kept coming back when they died like plants frequently do in a seasonal cycle. Finally, the Mayan gods got it right and created thinking, acting, and living people from maize dough and the gods' blood. In order to ensure the people were not too wise like the gods, Huracan filled their viewpoints and brains with clouds.
The Maya people who still practice the old traditions and religious beliefs believe that people could be destroyed again if they do not appropriately worship the gods. With the concept of all life exciting in a never-ending cycle, they also believe that some new people will come into being at that time.