The correct spelling of the word is customers, not "co stumers". The IPA phonetic transcription for this word is /ˈkʌstəmərz/, which can be broken down into four syllables: "kus-tuh-mers". The first syllable "kus" is pronounced like "cuss", the second "tuh" is sounded like the "tuh" in "turtle", the third "mers" rhymes with "furze", and the last "ə" is the schwa sound. It is essential to spell words correctly to ensure effective communication in written and spoken language.