Cut a four-ounce bar of Castile soap into very small pieces, no larger than 1/4 inch square - the smaller (as long as they're in cube form) the better. Place these in a heat-proof, non-metal container.
Heat slightly less than 1/3 cup of water until almost boiling. Pour the still hot water over the soap chips. Let it sit until it is cool enough for you to handle comfortably. Mix the soap and water with your hands. This should moisten the soap chips, but they should not be floating on the water. If they are floating, add a bit more soap.
Let the soap and water sit for about 9 minutes until mushy. If the soap cubes are still hard, set the bowl in a pan of water and reheat it gently until the soap is soft.
While the soap is melting, mix together the oils, and empower them with your magickal need. Then add 20-50 drops of the combined oils to the soap-water mixture. Very warm water evaporates the oils, so wait until the water has cooled. Mix them in thoroughly. The scent should be strong; if not, add more oils until you can smell them rather than the soap.
Divide the scented soap mass into 3 or 4 parts. Form these into spheres with your hands. Place each on a 9 inch square piece of cotton cheesecloth. Pull the ends tightly around the sphere, gather them at the top, and twist together. Tie the ends closed with a strong string. Repeat with each sphere.
Hang the soap spheres in a warm place for 3 days, or until the soap is completely hard. When the sphere's won't give to finger pressure, remove the cloth wraps. The soaps are ready to be used in ritual baths, or they may be wrapped in clean cheesecloth, labled and given to friends who would appreciate them.