Choose the work, not the house
A first opera should be under three hours, tonal, and have a plot that can be summarised in four sentences. Carmen, La bohème, The Barber of Seville and The Magic Flute all qualify. A four-hour Wagner is a magnificent thing and an appalling introduction.
Read the synopsis first
Not during. Spend five minutes before you go knowing who wants what from whom, and the evening changes completely. Surtitles handle the rest; every major house in this guide uses them, including the Met, which puts a screen on the back of the seat in front of you.
Sit high
Expensive stalls seats are for people who want to be seen. The upper tiers have better balance, a full view of the staging and cost a quarter as much. At Covent Garden the amphitheatre is the musicians' choice; at the Palais Garnier a restricted-view box gives you the room for very little.
Start with standing if you are unsure
A few euros at the Vienna State Opera buys you a place at the rail and a way out if you hate it. Nobody notices anyone leaving from standing, and the regulars around you will tell you more in ten minutes than any programme note.
What it actually is
Unamplified voices carrying over an orchestra to two thousand people, which is a physical feat that does not translate to a recording. That is the thing to listen for on a first night, more than plot and considerably more than costume.
