Most fabrics can be dyed, including sheers. Sheer is a type of weave, not a specific type of fabric. The actual fiber blend that is used to create the sheer can vary from silk to poly blends like cotton and other fibers. In general, silk will dye the best. Fabrics that are high in natural fibers will dye more easily than fabrics high in polyester. It is important to follow dye directions for the best results for the fabric you are trying to dye.
When selecting sheers for dyeing, look for sheers with a high ratio of natural fiber such as silk. Lesser expensive sheers are often polyester blends mixed with fabrics like cotton. The polyester in the mixture allows the sheer to drape well and not require ironing. Wrinkles can usually be eliminated by removing sheers from the dryer and hanging them warm. Polyester is less able to take some dyes than the natural fibers.
Preparing to Dye
Wash the sheers in regular laundry detergent to remove dirt and sizing. Dirt will affect how the dye attaches to the fibers, and sizing is a finish applied to fabrics by the manufacturer that prevent exposing the fibers to dyes. Washing fabrics will often shrink them slightly and will change the feel of the fabric. Use a hot water cycle on the washing machine for the best results, which will prepare the fabric for dyeing.
Making the Dye
Powdered and liquid dyes are toxic. Wear a respirator when mixing the dye with water. Use one package of powdered dye or 1/2 bottle of liquid dye for 3 gallons of boiling water. Dissolve and blend the dye and the water by mixing with a wood mixing stick. Use a plastic tub that is large enough for the fabric and dye. The tub will have dye stains later, so select one with this in mind.
Dyeing the Sheers
Calculate 3 gallons of dye/water mixture for each pound of fabric. Wear rubber gloves, and soak your sheers in very hot water. See that they are loose and untangled, and immerse them in the dye/water mixture. Stir the fabrics with a wood stick or spoon. You can try rolling the fabrics so that one area isn't on top all the time. Continue stirring until the sheers darken to the shade you want. Rinse the sheers in warm and then cool water until the water runs clear. Hang to dry on a clothesline. Cleaning your tub with a bleach cleanser will remove some of the dye staining.