Wyo. Stat. Ann. § 1-21-204

The date of appearance of the defendant as provided in the summons shall be not more than twenty (20) days nor less than twelve (12) days from the date of service of the summons. When the circuit judge has fixed the date for the appearance of the defendant he shall inform the plaintiff of the date and at the same time order the plaintiff to appear with such books, papers and witnesses as necessary to prove his claim.