Put on gloves, goggles, and long sleeves for protection.
Measure cold water and pour it into a heatproof pitcher.
Next, weigh the lye. Add the lye to the water and mix until dissolved.
Allow the lye solution to cool for 30 to 40 minutes until it reaches a temperature of about 100 to 110°F (38 to 43°C). To speed this up, you can place the pitcher in the sink filled with ice water.
Weigh the oils accurately. Melt the coconut oil in a stainless pot on the stove, then add in the other oils. This should warm the oil mixture to approximately 90 to 100°F (32 to 38°C).
If necessary, gently warm the oils in a stainless steel pot to achieve a temperature between 90 to 100°F (32 to 38°C).
Carefully pour the cooled lye solution into the oil mixture. Mix them by alternating between hand stirring and using a stick (or immersion) blender until the mixture reaches ‘trace’.
Stir in the essential oils. Then, pour the soap mixture into a mold. You can use a spatula or the back of a spoon to create a design on the soap’s surface if you like. Cover it (I use a piece of cardboard) and insulate with a towel or blanket.
Let the soap set in the mold for 1 to 2 days. Afterward, remove it from the mold and cut it into bars.
Place the bars in an open area to cure for 4 to 6 weeks before they are ready for use. And voilà! You have made your very own shampoo bars.