Thankfully, this achievement is relatively easy to get. Here is how you do it:
When you first start the table you will notice that in the center of the table are three drop down targets. The targets spell out the word: "G-A-S". You will likely hit one of these targets with your ball when you launch them; if not, you should eventually hit them, just aim for them with your flippers. Although this has nothing to do with obtaining the achievement, it opens up the top of the table, which is where you need to set your sights to get the achievement.
HOW TO UNLOCK THE ACHIEVEMENT: At the top of the table you will see 3 round lights that have the "N", "2" and "O", with each having a circular target above them. Just hit the target to light up each of the letters and the number.
Once you have completed this, then a red and yellow triangle will light up. You need to direct your shot in between the "N" and "2" targets. If you make the shot, your ball will go up the ramp and right into the Nitrous tank thereby unlocking the achievement (and likely obscuring your view of the table with the medal).
I think I did this in less than 5 minutes so it is really easy to do.