First off, I would like to clear up the long held and seemingly most mispronounced term for the outrigger booms. The proper word is 'iako (sounds like yah ko). I know, I know everyone says 'iaku (yah koo) which in Hawaiian means a run of fish or fish common to one area. I might seem picky on this but it is the proper term.
Next is the term Imua (ee moo ah), move forward. I have heard this term bastardized almost beyond recognition.
The handiest way in helping to pronounce Hawaiian words properly is to learn the vowel pronunciation:
A= Ah (as in above) E=Ay (as in pay) I=Eee (as in see) O=Oh (as in sole) U=oo (as in moon). This is an oversimplification but tends to help.