You can use it for wrapping paper, Christmas cards, or as stationary sets to give as gifts. You can find the ingredients at local crafts stores. All you need is ink, paper, a few paintbrushes, a dispersing agent to make the ink float, and a shallow tray or pan filled with water. Most of these items can be found at any good art-supply store. Inks that produce the most vibrant images are opaque drawing inks, and traditional sumi inks used for Japanese calligraphy.
Transparent inks produce a very faint, subtle image.
Createx liquid pigments also work well. If you don't know which inks are which, ask the clerk. A good choice for a beginner who wants to work on a small scale is a pad of practice paper for Japanese ink-painting. If you're having trouble finding the right kind of paper on your own, tell the clerk that you need an unsized paper. The bamboo-handled brushes used for traditional Chinese and Japanese painting work very well for suminagashi and are very inexpensive.