As with any type of construction, there are specific tools required. In this case, the only equipment needed is a large container to mix the cement in, a means of generating foam and a means of mixing the foam into the cement. The container can be a 55 gallon barrel (ideal for mixing a full bag of cement), or any large water tight, open container (depending on the size batch). I used an old feed tub acquired from a local rancher, which works well for mixing a half bag batch.
Equipment for generating foam and mixing can be purchased, or you can make and improvise equipment which will do the same job with less expense. You will also need an air compressor that will maintain 90 pounds of pressure to generate the foam. I already had the compressor and chose to make and improvise the foam generator and purchase a mixer attachment for my drill.
The contraption made of PVC pipe and assorted hoses and fittings at the top of the first photo is my home made foam generator. Assembled mostly from left over and salvaged items, the cost was really cheap. Operation is simple. Fill the tank with the dish soap and water mix, hook up the air compressor, open one valve to pressurize the tank then open the other valve to get the foam. The foam in question is pretty much the consistency of shaving cream. To make sure the mix and air pressure were correct, I weighed the foam on a kitchen scale. According to the instructions, the foam should weigh approximately 3 ounces per quart. Mine weighed just under 3 1/4. Not bad for the first try. Time to shut down the foam and mix the cement.
Half of a bag of Portland cement and 3 gallons of water into the tub for a thorough mixing. My old, slow 1/2 inch power drill worked great, though you can't see the actual mixer in this photo. The mixer is a standard drywall/grout mixer designed for use with a drill. It came from the local home improvement store and was not at all expensive. It took a few minutes for a good mix, which looked pretty thin to me and not much volume. I actually thought about dumping the rest of the bag in and making a larger batch. Really glad I resisted that impulse. 
Ready for the soap bubbles. This was the hard part for me. Having worked with concrete quite a bit over the years, it felt like a serious waste of perfectly good cement, but I pushed forward. Adding foam with the mixer running, I saw the volume begin to grow. Soon the approximate recommended volume was achieved. After turning off the foam, I mixed a bit more to make sure the foam was completely mixed into the cement, as it tends to want to float on top.
Time to pour the test batch. The form was something I put together quickly in advance using a couple of 2x4s and some thin scrap plywood. It was not really very solid but all it had to do was hold the concrete in long enough to cure. Thinking in terms of a tub almost full of concrete, my mind was thinking heavy. Sliding the tub closer to the form removed that thought. The coffee can I had on had to dip from the tub would not be needed. I simply picked up the tub and dumped the mix into the form.
Troweling the surface was interesting, and not at all like working with concrete. The texture and flow was more like, you probably guessed it, shaving cream. Actually, if you bake and have worked with meringue, it is more like that. Still trying to wrap my head around working with something that looks like concrete and works like meringue, but I may have to get used to it. Time to wait for the curing process.
Your questions and comments are welcome, and I will do my best to explain. I can hardly wait to show test results. Thank you for your time and please stay tuned for part 3.
For more information on Aircrete, I have included a website which I found very helpful. They give recipes and helpful tips as well as options for purchasing equipment, etc.
http://www.domegaia.com/how-to-make-aircrete.html
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