Prepare mold, lining it if necessary.
Weigh and combine the coconut oil and olive oil in a large stainless steel pot. If coconut oil is solid, heat just until melted and cool to 90-110 degrees F.
Weigh the water and lye. Go outside, and after donning safety protection (safety goggles, gloves and a mask), slowly add lye to the water (never add water to lye!), stirring until dissolved. Be careful to stand back from the mixture as you are able in order to avoid breathing the fumes that are created during the initial mixing process. Cool to 90-110 degrees F.
After oils and lye water are cooled, don your safety gear again and pour lye water into oils in the stainless steel pot and blend with an immersion blender on and off in intervals until the mixture reaches light to medium trace (a thin line that can be seen in the light as the soap is drizzled over the batch).
Add essential oils and blend until incorporated.
Pour into mold and insulate by wrapping in towels or a blanket, then set aside in a warm place for 24 hours. Depending on your mold, you may want to place it in a small box or shoebox to protect it before wrapping.
Remove soap from mold, cut and cure for 4-6 weeks (let air circulate around bars as they cure).
Shred one bar very finely and combine with 2 pounds baking soda and 2 pounds borax. Mix thoroughly, wearing a mask to limit inhalation of powders. Start water in the washing machine and add ½ cup laundry soap mixture before adding clothes.