There is no wrong way to drink rum, but a few small choices make it taste better.
Neat
Pour a small measure into a tulip-shaped glass or a small tumbler. Let it sit for a minute, smell it first, then take a small sip. Aged rums reward this treatment, with notes of oak, vanilla and dried fruit.
On the rocks
Add one large cube. Large ice melts slowly, keeping the rum cold without watering it down too quickly. A strip of orange peel is a nice touch.
With a mixer
Rum and soda water, tonic, ginger beer or cola with a squeeze of citrus is a classic long drink. A good starting point: 50 ml rum, a squeeze of lime, topped with about 150 ml of mixer over plenty of ice. Try Pink Dream & Tonic or Lychee Bliss & Soda.
In a cocktail
Shaken drinks such as the Daiquiri want fresh juice and plenty of ice. Stirred drinks such as an Old Fashioned want patience and a good cube.
Pace yourself
Sip slowly, drink water between rounds, and never drive after drinking.
Enjoy responsibly.