The first step in creating your own pop art canvas art is to find an image or photo. Warhol created his silkscreen prints from a variety of sources and subjects. There really is no limitation on subject matter at all when you consider that Warhol's work ranged from Coca-Cola bottles to Marilyn Monroe. The Andy Warhol style is characterized by simplified details and large blocks of bright colors. This can be done with the tools in most image editing software, but if you're looking for something more instant you can browse the web for a company that will convert and print your image onto canvas.
If you are a fan of pop art then you're probably already well acquainted with the work Roy Lichtenstein. Roy Lichtenstein became one of the leading pop artists of the sixties with his comic-strip paintings. Drowning Girl 1963 is one of his better known works and is a good example of the design features in his most famous pieces. He employed thick lines, bold colors, and thought bubbles. His work also often included boxed captions and words such as "WHAAM!" commonly found in comic books.
Benday dots were Lichtenstein's trademark. Benday dots are a printing process which combines two (or more) different small, coloured dots to create a third colour. Back in the day, pulp comic books used dots in primary colours to inexpensively create the secondary colours such as flesh tone. Artistic techniques for creating these dots varied and whilst Warhol screen printed onto canvas Lichenstein preferred to use perforated sheet metal.
Today, personal computers are powerful enough to create photo-tiled pictures in a relatively short amount of time. And despite the patents of most image editing software, there is a lot of free and inexpensive software, as well as web-based tools, that you can use to make a photo mosaic image from your own collection of personal photos. The larger your collection of source images, the better your home made canvas art will turn out.