NOTE! I am in no form or function, a foot doctor of any kind or sort. If you have a pre-existing or eminent foot condition, do not consult me about whether or not that I would recommend this for your treatment! The only thing I can testify to is that this instructable resulted in a helluva lot more comfortable a shoe than a pair with dual busted air bags.
Step 1: Materials!
Pair of busted air sneaks (Mine was all a single cushion in each sneak.) Bought at Goodwill for $6!
A pair of sandals (Preferably ones that compliment the color pattern on your shoes.) Walmart and Old Navy have these cheap sandals for $2.50 to $5 on average, and I'm sure you can find a sale, or even at Goodwill!
Exacto blade or other sharp knife (You'll need to cut the foam, and possibly the shoe.)
Pliers (for yanking the busted air pillow out)
screwdriver or other device for scraping (my sneaks had a bunch of foam gunk that used to hold the pads in place, and it had done a very poor job!)
Glue (If you decide you absolutely need glue to hold your new pads in, get something strong, long lasting, and most importantly, flexible! These are your shoes you're walking in, not blocks of concrete.)
A strong man (or woman!) Hubba hubba.
Step 2: Identify!
If yours has no such hole as the ones I'm demonstrating upon, go ahead and take that knife to slice open the side where the cushion should be. (It is a busted pair of shoes after all.) Careful not to cut yourself!
Step 3: Yank!
Step 4: Measure Twice, Cut, Well, Probably Half a Dozen Times.
Hold the air pad across the sandal. (Hopefully over a part with no holes)
Use a pen or tip of your razor, exacto, knife thing to trace a LOOSE pattern!
This is a foam pad we will be inserting and not another air pad! Since it is different it will feel different and fill out the space differently! Notice how I left off that bit of 'leg' on my pad. This was to both make the pad easier to insert and to provide just enough give for my feet to walk into and out of! You may also want to taper the edges of the pad but I would only do this on the insides of the "H" shape, as the thick edges will assist in keeping the pad inside the heel compartment of your shoe.
When cutting keep in mind that the bag is flattened, and was probably not as wide (say roughly a centimeter difference at most) as when it was filled with air! And don't be too frightened by how thick the sandal is compared to the bag either for the same reason. More cushion for the pushin, as they say, in the next step.
Step 5: Shove It!
Look inside the gap first and determine where there is the most space at. More than likely it will be towards the toe area but check anyhow..
Push as much of the pad straight into the gap, instead of into the space it is supposed to fill. When it has almost reached the other side, pivot it into the space it should normally fill.
Begin to stuff the other side in. Do not worry if it is not fully pivoted. If you have a gap on either side of the heel, convenient! Use your fingers to assist in shoving/pulling. (I would not recommend pliers at this stage, as you'll very possibly just pull the new pad into little shredded bits!)
If it's not going in, try folding the pad as pictured, you can straighten it out when it's fully inside the shoe.
POP! It's in! Make sure it's not too loose inside the heel compartment and that it is aligned properly to the way the previous bag was. Add that rubbery glue if needed on the side facing the rubber sole first to see how it adheres to the shoe and not provide your heel with gluetastic discomfort.
Step 6: Repeat!
Then you're done! ^_^ Enjoy your newfound comfort.