As with most games, blackjack has a few rules of etiquette that help both the player and the dealer conduct a quicker, cleaner game every time; here are a few of those unspoken rules.
When placing bets, it helps to place your bet in one stack of chips before you place it in the betting circle; as no cards can be dealt until your bet is made, it can be tricky for a dealer to have to wait for you to put individual chips on the betting circle until you’ve found the right amount to bet; make your bet in one swift motion. Also, when placing bets, try to bet even amounts if at all possible; although some casinos do have half dollar chips or $2.50 chips for blackjack (as it pays 3:2, and tables with $5 limits will have to pay back $7.50) some will simply round down, and it also serves as a convenience to your dealer; if you’re betting $200, it’s easy to pay out $300; not so much if you decide to bet $215.
Making hand motions to indicate betting actions is actually the preferred way of declaring actions in blackjack; these physical declarations are easier for pit bosses and security teams to read than simply looking at your lips. To hit, tap the table in front of you, point at your cards, or scrape the table towards yourself. To stand, wave your hand over your cards from left to right or right to left, as long as you do it the same way every time; dealers are perceptive people, and will grow quickly accustomed to whichever mannerisms you choose to declare action with, so stick with them throughout your session.