Iktomi is the spider trickster of the Lakota, a figure of the oral tradition who is greedy, vain and easily fooled, and whose stories are told as cautionary tales. Zitkala-Sa collected and retold them in Old Indian Legends (1901), a literary retelling by a Lakota writer rather than a neutral ethnography. He is not a deity and is not worshipped, and the lesson is the point of the story. The winter telling is the tradition's frame.
Modern Practice
Iktomi is kept in the winter stories, and the practice is the telling and the lesson, not an invocation. Tobacco and food shared are the offering, and the story is told to teach. He is not a 'trickster archetype' to be worked with.