Let’s start with the basics of social drinking etiquette. First, make sure the glasses have alcohol in them – the more superstitious of your French guests might be horrified to toast with water (‘quel horreur!’). Also note that a French woman would never serve herself wine. Gents, step up!
Next, someone, usually the host, might say levons nos verres (‘let’s raise our glasses’) to kick-start a toast before everyone can happily trinquer (clink glasses).
The most common versions of ‘cheers’, are santé or tchin while any of the following can also be used, depending on to whom you are raising a glass: a simple à la tienne (‘to yours’ or ‘to your health’); à la vôtre (‘to yours’ but in more formal fashion, perhaps to an elder family member or little known acquaintance); à votre santé (‘to your health’, formal) or à ta santé (‘to your health’, informal).
Always remember to keep eye contact with whomever you are clinking glasses – it’s bad form to have a vague gaze, as historically it implied you might have something to hide (perhaps you have poisonous intentions!) – and never cross arms with your co-drinker.
As for the drink itself, never over-fill a glass and on the rare occasion the wine is corked, it would be very bad manners for a guest to declare le vin est bouchonné.
On Christmas Eve, during the famously lengthy Réveillon dinner, after midnight mass a jolly ‘Joyeux Noël’ does the trick, while at New Year, say ‘Bonne Année’.
Of course, none of this really matters if your host is a genial type and you have minimal language skills at your disposal – if all else fails, just nab a glass of Champagne and smile a lot.
If the New Year’s party has been a success, the next day, Le jour de l’An (New Year’s Day) you are more likely to request un verre d’eau or two.