Cover a flat area with newspapers or other protective covering.
Fold your tissue paper in a way that will make it easier to unravel once you are finished. Make it as small or as large as you want.
Put on your gloves.
Use an eye dropper and dip it into the food color that you want. Have a different eye dropper for each color or wash one thoroughly between colors. Or, pour some of the food color out into small ramekins to make it more accessible.
Squeeze one drop of the food coloring at a time over the tissue until you get the color you want. Repeat this until you cover as much of the paper as you want.
Blot with a paper towel to remove any excess color.
Unwrap the tissue paper carefully and let it dry flat.