Garbage Santa will reward you for learning this skill.
He'll put all kinds of nice inflatable stuff out at the curb for you.
Step 1: Inflate
Big airmattresses often have a big deflation cap and a smaller inflation valve. I usually use the big cap.
One handy trick to know is the mattress inflates a lot faster if you blow the air AT the big intake instead of IN the intake. That's because the air jet from your blower entrains a bunch of surrounding air and sucks it into the mattress along with it.
Step 2: Cap It
Because the air mattress has so much surface area only a few psi are needed to inflate it properly (or pop it). (pounds per square inch * square inches = many pounds)
Next we'll find the leak. One way is to paint soapy water all over it and look for big soap bubbles. It's a sunny day so I'm going to take it swimming and look for bubbles in the water.
Step 3: Go Swimming and Find the Leaks
This is the first sunny day after a lot of rain so the sun's glare is blinding me.
Also my nordic cave-fish ancestors never got exposed to direct sunlight and evolved away their tolerance for it.
People who can be exposed to sunlight without getting sick don't need to make up stories about being the "master race".