Graffiti uses certain conventions with common techniques.
It's difficult to pinpoint exactly what graffiti is. Proponents claim that it has developed into its own in-your-face art form, which numerous gallery exhibitions and imitations seem to prove. But it is also unquestionably a nuisance to some, an eyesore to others, and it is still prohibited by law in most states when performed on public or private property. Certain techniques have come to define this unique form of expression.
Preparation
Graffiti is typically performed using multiple, multicolored cans of spray paint to create an image or "tag" on a vertical surface like a wall. One of the most important aspects to getting a successful piece or "throw up" is planning. Before you begin, have a solid idea of what you want the finished piece to look like and get it there. Sketching out the piece ahead of time helps tremendously. Practice the piece, spray paint and all, before you attempt the real thing. Practicing on canvas in an unhurried environment is ideal.
Can Techniques
Any traditional graffiti artist knows manipulate a spray-paint can to the best of his ability, and simply knowing spray can greatly affect the way the piece looks. For example, experiment with tilting the can at different angles to the surface of a wall to find out what effect each technique has. Spraying at 90-degree angles gives a more diffused paint spray, whereas holding the can horizontally can make for a more concentrated line. Another technique to master is distance: Holding the can close to the wall will give a sharp, crisp line, and holding it far away will make the spray light and spread out. Many basic graffiti techniques can be mastered by learning properly use a spray paint can.
Outlining
The outline serves as the structure of your piece: It's what gives it definition and makes it recognizable to those who know where to look. Many writers start their piece or "throw-up" here. The outline should look sharp and defined. Thus, the best can technique is to hold the can very close to the wall to get a concentrated and relatively thin line. Try to practice this ahead of time; keep an eye on proper proportions and ensure that outlines are smooth and fluid. Outlining can also be done at the end of the piece, in order to sharpen and redefine the original lines.
Filling
This is what gives any piece of graffiti life. Filling involves spraying colors within the outline, almost as if you're filling in a giant, vertical coloring book. For this process, the precise can distance and concentration depends on the piece, though generally you can use less caution than with outlining. Use a skinnier spray paint cap, move right along the outline, and point the can 45 degrees to the inside in order to avoid cutting in, or going outside your outline lines. For larger spaces, you can use less caution and a fatter cap.
Fading
Many pieces of graffiti art use multiple colors, sometimes even colors that gradually fade into other colors. Fading requires a light mist of spray where the two colors meet. You might accidentally go too harsh with one color. This is fine, as long as you compensate accordingly with the other color. Then, once the fade looks good, fill in the two sides more fully with each color, keeping the fade concentration where it is.
Shading
Shading can give your piece more definition and character, and can make it appear 3D. Shading uses a similar concept as fading, except that you're trying to make it look as if there's a shadow rather than another color. Use black or a darker version of the original color for your shadow. In order to shade correctly, decide where you want the shadows to fall (on the right, left, top, or bottom) and shade this area of every part of the entire piece or throw-up. Use this same technique to highlight a certain side by fading to white or a lighter version of a color on a particular side throughout the piece.
