The word "shimmin" is spelled with two "m's" to represent the double consonant sound at the end. It is pronounced /ˈʃɪmɪn/, with the "sh" sound at the beginning and the short "i" sound in the middle. The "-in" ending is pronounced with a short "i" sound followed by the consonant sound "n." This reflects the standard English spelling of words ending in "-in" such as "kin," "tin," and "win." Overall, the spelling of "shimmin" follows the basic rules of English phonetics.