At a blackjack table, your hands do the talking. Say "hit" all you want, but the dealer is trained to watch for a gesture, not a word. It trips up first-timers more than the strategy does. The good news: there are only four signals you actually need, and you can have them down before you ever sit.
It feels strange the first time. You're talking, and the dealer is waiting for your hand to move. Two reasons it works this way. The cameras overhead, what everyone calls the "eye in the sky," record every gesture, so if a dispute ever comes up there's no arguing about what you meant. And a crowded pit is loud. A clear gesture cuts through noise that a mumbled "stay" doesn't. Your hands are the official record of your decision, so make them clear.
Tap or scratch the felt
Want another card? Lightly tap the table behind your cards, or scratch toward yourself, like you're brushing crumbs off the felt. In a face-up game you can just point at your cards. The dealer drops the next card.
Wave flat, palm down
Done taking cards? Hold your hand flat, palm to the felt, and wave it once sideways over your cards. One clean motion. The dealer moves on to the next player.
Second bet + one finger
Place a chip equal to your bet beside the original, not stacked on top. Hold up one finger: you get exactly one more card, then you stand automatically. When to double is its own decision.
Second bet + two fingers (V)
Dealt a pair? Put a matching bet next to the first and make a V with two fingers. The dealer splits the pair into two hands and deals a new card onto each. When to split matters; "Aces and 8s, always" covers most of it.
That's the whole vocabulary. There's a fifth, surrender (give up half your bet on a bad hand), but most tables don't offer it and it's usually done by saying "surrender" plus drawing a finger across the felt behind your cards. Skip it until you're comfortable.
The signals shift slightly depending on how the cards are dealt, and it comes down to one thing: do you touch the cards or not.
If you can't tell which game you're at, look at your first two cards. Face up? Don't touch. Face down? One hand, and follow the dealer's lead.
Before you can signal anything, you need chips. Walk up to an open seat, wait for the current hand to finish, and lay your cash flat on the felt. Don't hand it to the dealer; like at a craps table, casinos require money to be placed on the table so the cameras see it. The dealer counts it out loud and slides your chips over. Put your bet in the betting circle in front of you, and you're in the next hand.
Nobody at the table learned this from a book; they learned it by doing it a few times and watching the dealer. The signals are muscle memory after about ten hands. The fastest way to get there without a $15 minimum riding on each one is to run those hands first with nothing at risk, so the only new thing at the real table is the felt under your fingers.
No signup, no money. Drill hit/stand/double/split until the choices are automatic, then the signal is the easy part.
The overhead cameras record every gesture, so a dispute can be reviewed with no argument about what you meant, and a clear gesture beats a voice the dealer might mishear in a loud pit. Your hands are the official record.
Hit: tap or scratch the felt toward yourself (or point at your cards in a face-up game). Stand: wave your flat hand, palm down, once over your cards.
Both start with a second bet placed beside the first. Double down: hold up one finger for one card. Split: make a V with two fingers.
Only in a face-down hand-held game, with one hand. In a face-up shoe game, never touch them.