The talc powder is to be applied to the tattoo after it has dried. The powder helps to keep the tattoo from fading. The 70 percent alcohol is to clean the airbrush gun and glass bottles with after you are done. Airbrushed art used to create tattoos will last for 7 days on the norm. Now if you have extremely oily skin it could start to fade in a couple of days. This will help you to learn more how to use the airbrush to render broad designs as well as fine detail. Now that you can render the shapes you should move on to using stencils. This will give you a feel for stencils as most beginning airbrush artists will use stencils to create their airbrush art. Practice using stencils on a cheap surface and still using your black paint. One way is that you can use stencils or masks to airbrush your artwork on to your project. The other way is that you can freehand the design onto your project without the use of stencils or masks. Most stencils and masks that you purchase are reusable. The stencils are made from different material depending on what the stencil will be used for. A damages needle can be disastrous to your ability to create high quality art, because if you are unable to straighten a bent needle back out or the needle should break completely you will not be able to finish your airbrush art until you can get a replacement. If you do end up bending your needle you can try and straighten it with either pliers. The prep work that you do will be determined by what type of surface you will be airbrushing. The prep work to the surface will ensure that the paint sticks to the surface and that nothing is interfering with the airbrushed design. For airbrushing t-shirts, sweatshirts, denim and other natural fibers you first need to wash the material. The internal mix is when the air and the paint both mix inside of the airbrush. This will create a atomized fine dot spray pattern. This makes the internal mix a good choice for fine detailed work in your airbrush art. The point at which they come together is in the head assembly. The external mix is where the air and paint come together outside of the head assembly or the fluid assembly.