The Hawaiian diacritics consist of the ʻokina or open typesetterʻs quote, and the kahako, which is the line (macron) above a vowel.
You do not need any special software or keyboard to type the ʻokina. The ʻokina is supported with the regular U.S. keyboard. To type the ʻokina:
Press and hold the option key, then press the ] (right bracket) key
To type the kahako, you need to enable the Hawaiian keyboard. The Hawaiian keyboard is built into the Macintosh operating system. The following instructions apply to Mac OS 10.6 and above.
To enable the built-in Hawaiian keyboard:
To use the keyboard to type the kahako: