Practical Restaurant Service
Sequence is the answer
Service questions test order, safety and composure more than trivia. Know the full arc: mise en place (glassware polished and inspected, ice, linen, decanters, corkscrew, POS), greeting and seating, menu presentation, order taking, wine service, food delivery and clearing, payment and farewell. Within wine service the fixed order is: bring the bottle and confirm it is what was ordered, present the label to the host (not the cork), cut the capsule below the lip, wipe the neck, insert and extract the corkscrew gently, wipe again, pour a small taste for the host, then serve guests - conventionally host last, guests in a clockwise order.
Sparkling and decanting
Sparkling: chill thoroughly, cut the foil, loosen the cage while pointing the bottle away from people, hold the cork, angle the bottle 45 degrees, turn the bottle rather than the cork, and ease it out with a whisper. Never use a corkscrew on a sparkling cork. Decanting old wine is a sediment operation: stand the bottle upright, decant over a light source and stop at the sediment. Carafing young wine for air is a different act.
Faults at the table
Inspect, agree, replace - do not argue. Know the signatures of TCA, oxidation, refermentation and heat damage, and how to say so diplomatically.
Traps
Questions probe who tastes the wine, whether to present the cork, decanting versus carafing, pour order, and serving temperature. Whites and light reds are served cooler than most candidates state; sparkling is coldest.
Worked example
A 1996 Barolo arrives with sediment. Stand it upright for a day, decant off the sediment into a narrow decanter over a candle, and serve promptly - old reds can fade with extended air, so do not leave it sitting for an hour.