Combine your lemon juice and sugar in a bowl and mix well. In the same bowl (or in a cup) Add in your orange juice and 1 ounce of rum. Stir well. Fill a 16-ounce cup half full of ice and pour your mixture over the top of it. Using a spoon, float the last three ingredients in order. This means you will slowly pour each liquid over the back of a spoon so that it doesn’t mix into the drink too much.