Pop your lime in the microwave for a few seconds or until slightly warm, this really helps any citrus release their juices. Cut it in half over your juicer or directly over the drink shaker if squeezing the lime by hand because it will drip when cut. Juice the lime. Use the pulp side of the juiced lime rind to rub the rim of your margarita glasses and then dip them in the salt. The sugar from the lime juice helps the salt stick to the glass. I used to try to do this with water and I could never figure out why my salt wouldn’t stick. Duh.