In one sentence, describe what the following article is about:

Although it may seem that any glass will do, to enjoy a truly perfect glass of Guinness you must use a tulip glass.  The shape of a tulip glass is perfect for allowing the nitrogen bubbles to circulate from the bottom and back up to the top. Although any size will do, a 16oz glass, otherwise known as a pint, is generally agreed upon as the classic size for the drink. Pour until the glass is about ¾ of the way full, in one slow smooth pour.  Using the 45 degree angle keeps the Guinness from frothing and allows for a better head. Be sure to keep from pouring straight down, as it will create a fisheye in the top of the foam and large unwanted bubbles After pouring, let the Guinness set for a minute or two so the head can develop. The nitrogen bubbles become distressed by the movement of the pour, and will gather in a creamy foam at the top of the drink when allowed time to settle. Fill the glass the rest of the way up, so that a dome effect is created at the top of the glass. Although good on its own, try the beer paired with seafood for a delicious combination.

Summary:
Choose the right glass. Pour the drink into the glass at a 45 degree angle. Let the beer rest. Top the Guinness off. Enjoy your Guinness.