Wyo. Stat. Ann. § 18-1-302

Whenever at least three hundred (300) qualified electors who are property owners desire to organize a new county for the purpose of establishing a county government, they may petition the governor to appoint three (3) electors residing within the boundaries of the proposed new county to act as commissioners in organizing the new county. Attached to the petition shall be affidavits of at least two (2) qualified electors residing within the boundaries of the proposed new county stating that the petitioners are qualified electors and property owners residing within the boundaries of the proposed new county and that the requirements of W.S. 18-1-303(a) and (b) have been met.