Yes, you can improvise! A tightly sealed jar (like a mason jar) can serve as a shaker. For measuring, standard kitchen measuring spoons can be used (e.g., 2 tablespoons for 1 oz). While dedicated tools offer precision and ease, these substitutes will get the job done for a beginner.

Absolutely. You can substitute agave nectar with simple syrup (equal parts sugar and water, heated until dissolved and cooled) or even orange liqueur like Cointreau or Triple Sec. Simple syrup will maintain a clean flavor, while orange liqueur will add a subtle citrus note and sweetness, making it a Grand Margarita style.

To get a perfect rim, rub a lime wedge only around the outside edge of the glass. Then, gently dip just the outer rim into a shallow plate of salt. This technique helps prevent salt from falling into the cocktail and ensures a clean, crisp salted edge.

The key is the ratio. Ensure you're using a jigger or precise measurements for the tequila, lime juice, and agave nectar. If it's too tart, add a touch more agave. If too strong, more lime juice can mellow it. Always use fresh lime juice for the best balance.