Tip: Any color that you cover with tape will remain unchanged throughout the process.
Start with a white egg or one dyed a pale color. Band the egg twice lengthwise with a 1/4-inch-wide masking tape, repositioning as necessary to get a tight fit. Firmly rub the tape with your fingernail or a burnishing tool so that the dye can't seep underneath.
Dip egg into dye, raising and dipping until the color deepens as desired. Blot egg with a paper towel. Let dry ten minutes. Remove tape.
Band the egg's width with tape at its widest point, then repeat to make smaller circles around each end. (Try alternating wide strips of tape with narrow ones.) Burnish, dye, and dry as before.
Remove tape. If you used a raw egg, carefully blow out contents.