Best practice "Hello, good evening! May I help you with my wine list?"

As a sommelier, that is how I greet a table of guests at the beginning of their evening. The responses I receive range from the sublime to the hilarious.

When a diner replied, "What's the soup today?", I offered to send over their waiter. For that, I got a telling off: apparently, I should have known the answer to anything a guest could ask; the diners later complained about my attitude.

That table's expectations were at odds with what I'm told at the back of the house: there, the mantra is, "let the other staff do their jobs, too".

Other responses to my opening line have included:

"Go away, we're not ready."

"We don't like our table."

"The air-con is too cold."

"Can you take our order?"

To the last one, I sometimes reply, "Let me send your waiter over," if I see one available close by - otherwise, yes, I can take the order.

Some guests say, "We don't drink wine."

I then ask if they'd like some mineral water or a mocktail while discreetly removing the wine glasses and list from their table.

My favourite request is, "May we speak to the sommelier, please?" To which I reply, "Yes, how can I help you?" Often, they repeat their request and I repeat my reply.

Finally, the penny drops.

On occasions like this, I wonder what guests expect a sommelier-in-residence to look like. Quite often, we are lumped in with waiters, even though we are dressed differently. We are not quite seen as management material and are frequently confused with the maître d'.

Here's the minimum you should expect from a sommelier: extensive knowledge about various wines (especially those on his or her list); the ability to skilfully open a bottle and distribute its contents; he or she to introduce themself to a table; in-depth knowledge about the cuisine on offer and how each dish would pair with the wines on his or her list; and that he or she has checked with the waiter to see what the table has ordered, rather than asking the guests what they've chosen.

He or she should know if a wine on the list is no longer available. This doesn't always work perfectly, as when there is only one bottle remaining, it may already have gone to another table. On a recent Saturday evening, I spent 10 minutes looking for a wine that I was sure I had three bottles of, before noticing a guest now had them all on his table.

The sommelier should also inform the guest if they've had to change a vintage but haven't had time to reprint the wine list. Usually when this happens, the guest will expect the wine to be cheaper if the vintage is younger - even if I tell them that the year we're currently selling is better than the one it replaced. Nobody complains if you offer an older vintage.

And what do sommeliers expect from guests? I'm always grateful to those who make my evening interesting - the ones who tell you what they like, and what they wish to spend on a bottle. I'm happy when I introduce guests to a wine they haven't tried before and they enjoy it as much as I do.

The best thing that can happen to a sommelier is when a guest offers them a sip of a rare bottle.

Nellie Ming Lee is a food stylist and part-time sommelier studying with the Court of Master Sommeliers.