Through the use of an online tool, taking an image and blowing it up to be printed on individual pieces of paper that can then be pieced together to form a large picture.
I'm going to rasturbate a picture of the sky and tape it onto my ceiling.
creating a picture larger than a piece of paper by printing out the picture in sections sized to a page, then connecting those pages in the proper order.
Resizing an image larger to fit on many pages. These are then printed out and placed side by side to recreate a large poster of the original image. Usually the image is also modified to be made up of small dots, similar to old comics.
"That poster is huge, it must have cost you hundreds."
"No, Wendy taught me about rasterbating, it only ended up costing like $10."