The ordinary and hourly rate for each employee, then every day at the rate the Employment Act sets — 1.5 times beyond the normal hours, more on a rest day, more again on a public holiday — with the month totalled and the 104-hour limit checked.
The month, your working week and your state. The working week decides which days are rest days; the state decides which days are public holidays, from the same gazette table LTT CutiCal uses. Nothing here is uploaded.
Overtime is any work beyond the normal hours of a day (at most 8) — Employment Act 1955 s.60A. Work on a rest day (s.60) and on a public holiday (s.60D) has its own rates. The Act limits overtime to 104 hours in a month. A week has one rest day (s.60(1)); on a five-day week the other day off is an off day, which the Act does not price — only the hours beyond the normal hours are statutory overtime, and anything for the day itself comes from the contract.