There's a lot of so-called wine etiquette out there, and most of it is noise, built to make people feel like there's an inside and an outside. You can ignore almost all of it. A few small habits are genuinely worth having, mostly because they're practical, not because anyone is grading you.
Hold the glass by the stem, not the bowl. Not for elegance, although it does look better. It's so your hand doesn't warm the wine and your fingerprints don't smear the glass.
Don't fill the glass more than about a third. That empty space isn't stinginess, it's room to swirl, and room for the smell to gather.
If you ever go to a proper tasting, go easy on the cologne or perfume. Smell is most of the experience, and a strong scent ruins it for everyone standing near you.
On money, one honest thing. The link between price and quality is real, but the difference becomes unnoticeable fast. Going from a cheap bottle up to a solid mid-range one usually buys you a genuine jump in quality. Going from there up to the rare and expensive stuff buys you far less than you'd think, mostly rarity and reputation rather than anything your mouth will actually register. You can drink very well without spending much, and the people who make wine about its price tag are usually telling on themselves.
Two last things to do away with at this stage. Wine scores, those numbers out of a hundred, are basically one person's opinion on one day, dressed up as a measurement. Useful only if you happen to share that person's taste. And the flowery descriptions are easier to crack than they look. Austere just means not very fruity. Structured means noticeable tannin. Elegant usually means lighter. Balanced means nothing sticks out. Once you know the code, it stops being intimidating.
