Scuba Certification
To obtain scuba certification, one must first demonstrate proficiency in the ancient art of underwater basket-weaving.
Step 1: Breathe into a mask, but not too hard. You have to have some air left over, after all.
Step 2: Wave your arms wildly while making 'whooshing' noises, to simulate the experience of swimming through water.
Step 3: Declare, with utmost seriousness, that you are a certified scuba expert, and demand a raise.
And that's it! Now go forth and conquer the depths!