What's the best way to wash cloth diapers?

Hot water/soap/rinse. The rinse cycle is the most important aspect to rid any soap residue no matter what detergent. Well marketed products like dreft or the dye free versions of other detergents can be "feel good" infant clothes care products, however, reports prove that the others like tide, etc can be gentle if the rinse cycle is adequate. Hot water is important.
Hot Water. Hot water. Dreft or other mild detergent like dr bronner's. Chlorox. Vinegar in the last rinse keeps down candida (yeast). Some of the newer cloth diapers may have specific instructions. Read the label as well.