First, find a table and check the minimum bet to make sure it's in your budget. Lay your money on the table and the dealer will exchange it for chips -- you don't even have to ask. (The dealer won't cash your chips in, though. You have to go to the cashier for that.)
Players take turns rolling the dice. If someone is rolling when you walk up to the table, you have to wait until the next "come out" roll before you can place your bet. As soon as a shooter sevens out (rolls a seven after a point has been established), the next player becomes the shooter. To place a Pass Line bet, you put your bet on the Pass Line before the shooter rolls his come out roll. Let's say you bet $5 (a "nickel" in betting lingo).
The shooter starts off hot and rolls a 7 right off the bat. You just doubled your money and now have $10. You can either take your winnings and keep your original bet on the table or else let it ride and double your bet (called pressing your bet). You decide to press your bet.
Now the shooter rolls an 8, so 8 becomes the point. Remember, you want to see another 8 before you see a 7. The dealer places a white puck called a marker puck on the number 8 in the Place Bets section of the table to mark the point. (When the black side of the puck is showing, no point has been established.)
The next roll is a 3, then a 5, and finally an 8 the hard way (two fours). You've just doubled your money again. Now you can either pick up your bet or place another one for the next roll. That's all there is to the most basic craps game.