Cut the top off the watermelon to create a lid. Scoop out the watermelon flesh and reserve 1/2 cup.

Combine juices: In a separate pitcher, combine the lemon juice, mango juice, and orange juice.

Fill the watermelon: Pour the juice mixture into the watermelon cavity and muddle with the watermelon pulp

Add tequila: Pour the tequila over the juice mixture.

Serve: Fill the watermelon with ice cubes. Serve immediately.