Prepare the Glasses:

1. Rub the rim of each margarita glass with a lime wedge to moisten it.
2. Dip the rims into a shallow plate of margarita salt until the edges are evenly coated.
3. Set the prepared glasses aside.

Sweeten the Lime Juice:

1. In a small measuring cup or bowl, combine fresh lime juice and simple syrup.
2. Stir the mixture until the sugar is completely dissolved.

Blend the First Batch:

1. Add one portion of frozen melon cubes (watermelon, cantaloupe, or honeydew) to a high-powered blender.
2. Pour in the sweetened lime juice, kosher salt, reposado tequila, triple sec, and watermelon schnapps.
3. Blend on high until the mixture is thick and smooth.

Add the Remaining Melon:

1. With the blender still running, gradually add the remaining frozen melon cubes, one small handful at a time.
2. Continue blending until the mixture is smooth and frosty.

Serve the Margaritas:

1. Carefully pour the blended margaritas into the prepared glasses.

Garnish and Enjoy:

1. Garnish each glass with a lime wedge, mint leaves, or melon balls for an extra touch of color and flavor.
2. Serve immediately and enjoy your refreshing Frozen Mixed Melon Margaritas!