Air mattresses come with automatic pumps that will fill the mattress with air in less than a minute. To know when you've filled just the right amount of air in the mattress, press down on the mattress with your finger as you fill it. When you can depress only about 1 inch down, it's ready to be slept on. Don't fill it up much more than that, because the extra pressure will cause a greater chance of bursting.
There are two ways to deflate an air mattress. You can put the opposite end of the of the automatic pump into it, and it will suck all of the air out of the mattress when you turn the pump on. This is the fast way to deflate the mattress. A better way to deflate is to simply open the air hole on the mattress and slowly roll all of the air out manually. Grip the back of the mattress with your hands and begin to tightly roll it as if it were a scroll. You'll hear the air push out of the mattress as you roll it all the way to the other side. This process will take just a couple of minutes, but you'll avoid any awkward creases that will develop as a result of using the automatic pump.
If you're going camping with an air mattress, you'll want something that will fit in your tent. A smaller mattress is also less expensive. It will typically cost between $25 and $50. These mattresses are comparable in size to twin size mattresses.
If you want a larger mattress for house guests, get a larger and more comfortable queen-sized air mattress. These mattresses are twice as high off the ground than camping mattresses and wider. These generally cost between $60 and $100.
There are also air mattresses that rest on top of a cot. Whether you're camping or housing guests, this option lets you sleep a few feet off the ground, as if you were in a regular bed. These "Space Saver" air beds usually cost between $75 and $100.
You can store an air mattress in its inflated or deflated form. If you use the air mattress more than once a week, leave it inflated and simply stand it against a wall where it will be be out of your way. Air mattresses are very light and are not hard to move from a horizontal to vertical position.
Storing an air mattress in its deflated form will save you some space, though. Remember to keep your pump stored in the same place as the deflated mattress.