1. Measure Everything
Bartending is closer to baking than savory cooking; it requires precise measurements for the final product to be perfect every time. Most bartenders use counting or jiggers; I recommend getting yourself a set of OXO angled mini-measuring cups for home bartending.
2. Control Dilution
The cocktail itself is defined as containing water, so water is an essential component of your drink. However, there is not one texture or amount of dilution that is perfect, so you must taste and get used to the different amounts of dilution and texture for each drink. Consider the rich, full-bodied texture of the brandy Alexander versus the taut, sleek body of the dry martini cocktail.
3. Taste, Taste, Taste
Good chefs taste their ingredients; so do good bartenders. Get to know the various spirits and mixers. When an ingredient calls for two ounces of London dry gin, you still have a staggering array of product to choose from. In the past I've had friends get together and bring one bottle each. Have a vodka, gin, or Bourbon party. That way learning doesn't cost an arm and a leg.
4. Use Lots of Ice
When you make a drink, don't skimp on the ice. This is where good, hard, dense cubes come in handy. Load up your shaker or mixing glass to the brim with ice. Making sure the cocktail is properly chilled is crucial to a well-made drink.
5. Garnishes Matter
Garnishes don't belong on the side of the drink--they belong in it. They should be working for their board. No lazy garnishes! Use only fresh garnishes that will enhance the drink. The Gin Rickey is a good example, the lime shell, once squeezed goes directly in the drink where the lime peel continues to flavor the drink.
6. Recipes Are a Baseline
I hate to say it, but some of my favorite bar books have recipes I find necessary to tweak and re-tweak before I'm satisfied. This requires a little extra research on your part; fortunately, you get to taste each result! Don't take the recipe for face value.
7. Muddle Softly
You know the saying, "Walk softly and carry a big stick"? Try this: muddle softly and carry a big stick. You needn't muddle limes, mango, or mint with such intensity that you obliterate the fruit or herb. In fact, you'll often draw bitter results. You only need to start the process. Shake and stir, and the alcohol itself will draw out the flavor.
8. Use Fresh Juice
This goes for all culinary endeavors--the fresher the ingredient, the better, more articulated the flavor. Don't believe me? Buy Roses Lime, Santa Cruz Organic 100% lime juice, and Mr. & Mrs. T Sour Mix, and taste them side by side with fresh lime juice. You'll be astounded at the difference.
9. Sweeten it Yourself
Everyone knows that the bright red color in grenadine is the result of the marriage of unnatural and unholy elements. Try making your own! Buy 100 percent pomegranate juice and sugar. Mix two-to-one sugar-to-juice by boiling the juice and adding sugar. You can create many different sweeteners, including cane sugar and Demerara sugar, each with boiled water at equal parts. This will steer you away from any mixture that starts with "high fructose corn syrup."
10. Shaken and Stirred
The principal methods to blend cocktail ingredients are to shake or stir. The rule of thumb that any bartender worth a shake of salt (no pun intended) will tell you is to stir liquors and shake juices, sugar, and egg whites. If the cocktail calls for two or three liquors, take the Manhattan as a prime example: it should be stirred. If it calls for juices and egg whites, like a Pisco Sour, shake vigorously to combine the ingredients.