Merchant licensing is governed by Wyoming State Statute §33-20-101 through §33-20-210. A temporary or transient merchant is described as, "All persons, firms and corporations, both as principal and agent, who engage in, do or transact any temporary or transient business, within in one (1) locality or more by traveling from one (1) or more places in this state, selling goods, wares or merchandise and who for the purpose of carrying on such business hire, lease or occupy a building, structure or car for the exhibition and sale of such goods, wares or merchandise." (W.S.S. §33-20-201).
So, if you are a traveling salesman Wyoming requires that you obtain a transient/temporary merchant license by applying with the County Clerk's Office.
Transient merchant licenses are valid for one year from the date of approval!