The first step is creating your screen. A screen consists of a wooden or aluminum frame with a fine nylon mesh stretched across it. For your first frame, use wood. Assemble a wooden frame large enough to cover your desired medium. This can be done with scrap lumber or pieces from an old picture frame. The frame should be flush and flat on both sides, so avoid decorative picture frames if you are using them for pieces. Once the frame is built, add the screen.The screen can be purchased at most hobby stores. For printing on cloth you should use a mesh count of 110 or 160. Paper printing will require a higher mesh count. Stretch your mesh tightly across the frame leaving two extra inches on all four sides and staple it down.
Preparing an image for printing requires some serious consideration. Be sure to choose images with high contrast. Silk screen printing is not a good medium for subtle tones. Once you have chosen your image, separate it into its component colors and convert each separation to black and white and print it out on a transparency. A separate stencil is necessary for each color. Alternately, if all you need for your reproduction is a single-color version, just convert the original image to black and white and print that.
Now you will need to burn the stencil. This must be done in a photo safe room, such as a closet. You can use a low wattage red light to see what you are doing, but no other light can enter the room. First, coat the screen in emulsion, available at most photo stores, using a squeegee to spread the emulsion evenly and thinly across the screen. Let the screen sit in the dark for about two hours.
Next, you need to expose the screen using your image. In your photo safe room, place the screen on a black cloth and lay your image flat on the screen. Find a piece of glass to fit your image and place that over the transparency. Using a 250-watt photo flood bulb, expose the image for about 15 minutes. After the exposure time you can turn the lights on and wash the screen thoroughly with cold water.
Repeat with each color separation.
To print the image you need fabric safe ink, a board and something to print on. Place your screen on whatever material you're printing on, pour the ink on the screen at the top of the image, and, using the squeegee, spread the ink evenly across the screen. Lift the screen and the image will be reproduced under it. You can print from this stencil as much as you like as long as you are careful to keep it clean.
With each separate color, be sure you have the image aligned precisely before applying the ink.