For the Cocktail 

1. Pour chilled gin into a coupe glass.
2. Add in tonic slowly (this will change the color).
3. Now add in lime simple syrup and stir with a bar spoon.
4. Add a lime wheel to the glass rim and place an orchid against the side of the lime wheel inside the cocktail.
5. Optional step: Using metal cocktail tongs, add in 1 to 2 small pieces of dry ice to get a bubbling smoke effect. Before enjoying, make sure the dry ice has completely melted or remove any remaining pieces.

For the Lime Simple Syrup

1. Wash the outside of the limes under cool water.
2. Juice the limes until you have ½ cup of juice.
3. Set the lime halves aside as you will use them later.
4. Place the sugar and water in a small saucepan. Add in the lime juice. Heat the syrup on medium-high heat, stirring until the sugar dissolves.
5. Remove from the heat and add the juiced lime halves into the lime syrup.
6. Cover the saucepan with a lid and let the limes steep for 1 hour.
7. Strain the lime syrup into a container through fine mesh strainer. Let the limes drain and squeeze them to get as much juice out of them as possible.
8. Let the syrup cool to room temperature, then pour it into a jar. The Lime Simple Syrup will keep in the refrigerator in a sealed container for up to 2 weeks or if you add a tablespoon of vodka or rum it will last longer.