Bourbons found at most bars include Wild Turkey, Maker's Mark, Woodford Reserve, Bulleit, Jim Beam, and Evan Williams, but you can also ask the bartender for a recommendation.
Next, tell your bartender whether you'd like your bourbon served "neat" (without ice) or "on the rocks" (with ice). Either way, you can expect a standard 1.5 ounce pour of bourbon.
For example, saying "I'll have Bulleit bourbon, on the rocks" will give you 1.5 oz of Bulleit over ice, unless your bartender is feeling generous and wants to give you more.
If you'd like to make your order a double (AKA a 3-ounce pour), just slip that info in after the brand by saying something like "Bulleit, double, on the rocks.”