In the
traditional silk-screening approach, you start with a
square wooden frame about the size of a T-shirt. Over this
frame you tightly stretch a piece of sheer fabric
(originally silk, now polyester). This is the screen. Over
this sheer fabric you put a thin sheet of plastic into
which you have cut holes where you want ink to appear on
the T-shirt. You can either cut the holes with a scalpel
(an arduous task), or you can use a liquid plastic coating
that's sensitive to ultraviolet light and "cut" the holes
with light.
Next, you place your T-shirt on a flat board and press the
screen onto the fabric. By coating the screen with thick
ink using a sponge, you cause the ink to flow through the
screen onto the T-shirt. For multi-color designs, you do
this multiple times, starting with the lightest color and
moving up to the darkest.
