You need just two things to create great frozen margarita-style cocktails — a sense of proportion and a blender.

If you lack the latter, you're on your own. But learning the proper proportions is easy. And once you've mastered that, you'll never need another recipe.

Step 1: Start with the alcohol. Tequila is the throat burner of choice, and it often is combined with orange liqueur, such as triple sec (any liqueur can be substituted, depending on the flavor combination you're going for).

You'll need about 2 ounces of tequila per serving. Another ounce of liqueur is nice. If you'd rather skip the liqueur, increase the tequila to 21/2 ounces.

And in case you don't have a measuring cup that does fluid ounces, 2 ounces is the same as ¼ cup.

Step 2: Now consider how to flavor your drink. It's nice to balance the bite of the tequila with citrus, such as lime juice (the traditional choice), lemon juice (especially refreshing), orange juice or pineapple.

Other acidic fruits, such as pomegranate or cranberry, also are good. Nonacidic fruits (such as watermelon) are fine, too, but you may need to add a tablespoon or so of lemon or lime juice to balance the flavors.

In some cases, whole fruit can be substituted for some or all of the juice. Use your judgment here. This works well with tender berries and pineapple, but not so great with apples or lemons.

Whatever your choice, aim for about ½ to 1 cup of juice or fruit per serving.

Step 3: Round out the drink with something sweet. Simple syrup (equal parts water and sugar heated until clear, then cooled) is traditional, but honey is splendid. Agave nectar (similar to honey) and maple syrup also are nice.

For quantity, you'll need to experiment, but if you like your drink sweet, use an equal number of tablespoons of sweetener as ounces of alcohol. So for a drink with 2 ounces of tequila and 1 ounce of triple sec, use 3 tablespoons of sweetener.

Step 4: The cold stuff. Use more or less ice depending on how thick a drink you want. The easiest way to do this is to measure out the other ingredients, add them to the blender, then add ice and purée until you're happy.

For more intense flavors, freeze juice and use that for some of the ice. Frozen apple juice would be great. Frozen juice concentrates also add intense taste and chill. Even better, freeze fruit such as melon balls or strawberries.

Step 5: Salt heightens the sweet and acidic flavors in most margaritas. But if you think a thick salty coating around the rim of your glass would be too intense, add just a pinch to the blender.

You can use a wedge of lemon or lime to wet the rim of the glass (which, once wet, is dipped in coarse salt), but it's even easier to dunk the rim in the pitcher after the cocktail is blended.

Not ready to invent your own margarita? Get blending with these easy and refreshing recipes. They don't always follow the rules above, but they are delicious. Each of the recipes makes generous servings.