Grab a case of your favourite light pilsner and some liquid blue food colour.
Note: You could attemt to make green beer with darker brews, but light beer results in a better green beer. Think back to your colour theory classes in high school
Pick a mug of your choice for you and your buddies. Pop it in a freezer for an hour to make sure that the brew becomes nice and frosty after you pour it. If you are a bottle drinker, just make sure your brew is nice and cold. Check out the Beer Fridges and Coolers post to help you decide what fridge you’ll want for your birthday.
After you open your bottle of beer or pour it in your mug, squeeze a few drops of blue food colouring into the brew. Don’t worry the food colouring is vegetable based and does not affect the taste of the brew. Blue food coloring achieves a better green than green food coloring when making Irish Green beer. This happens because beer is yellow, so when you add blue food coloring you will get a greener color than if you use green food coloring.
Note: Don’t be to hasty with adding too much food colouring to your beer. You might find that the blue mixes in a lot quicker with the beer and you could end up with a very very dark green beer.