How to taste gin:
Firstly, it’s a spirit, so go easy. Secondly, it’s not like tasting wine; with wine you’re looking to aerate it to release the flavors. With gin, the flavors are far more direct and not masked by other flavors, you want to locate the botanical notes to determine the dominant flavor compounds in gins.
Taste the gin straight around room temperature (about 12-15°C, 54-60 Fahrenheit).
Swill it around your mouth to cover your palate – good gin will have an assertive warmth, but no burn. Head and tail notes produce a burn which good distilleries remove in the distillation process
Add a splash of cold water. The water encourages the release of the botanical flavors within, as the oils are released into the water.
Taste it as you drink it and explore the flavors. All gins are juniper based and have botanicals superimposed, which can be quite diverse. As a rule, you’ll find pepper and licorice notes in Wood's Treeline, malt and lavender characteristics in Deerhammer's Bullwheel, cucumber in Martin Miller’s and Hendrick’s, spice in Williams GB and citrus in Tanqueray 10. So good luck in your quest and most importantly- relax and enjoy the process.