I recently made these for my girlfriend and she loved them. They are really easy to make and can be a fun project, even for kids.
I found the recipe online, but I've made a few adjustments.
Keep in mind that humidity, room temperature, oil viscosity, and other factors can affect how these are made. I would recommend a nice clean work space, such as your kitchen.
Additionally, if you have any minor open cuts or wounds, the ingredients will cause discomfort.
I used fairly common ingridents for mine. Some are more difficult to find than others. I had to visit 3 different stores to get all the supplies. Check your common grocery store first, but you may have to visit a health food store as well. Craft stores will likely have the fragrances, just make sure you buy the ones intended for soap making and not candles.
Recipe is two parts:
Dry ingredients: (By Weight , as measured on a scale.)
Baking Soda – 8 ounces
Citric Acid – 4 ounces (In Ottawa, I only found this at Rainbow Foods)
Corn Starch – 4 ounces
Salts – 4 ounces (I used epson salts)
Water – .75 tbsp
Essential or Fragrance Oil – 2 tsp (I used Apple)
Oil – 2.5 tbsp (I used Organic Coconut Oil, but even vegetable will work)
Food coloring – 2-6 drops. (Your color will look very dark in the emulsion, but will be light in the end. Start with a couple of drops first)
Mixing Bowl (Glass works best)
Mixing Spoon or Wisk
Small Mixing bowl (for wet ingridents)
Moulds (This can be anything. I've used apple shapped ice cube trays from the dollar store. They work alright but I suggest basic shapes for the first few attempts. I am on the look out for a round Xmas ornament personally. But you can also use plastic easter eggs, soap moulds, old muffin trays, etc…)
Begin by putting all of your dry ingredients into a big bowl. Get rid of any clumps, you want a fairly smooth consistency throughout the entire mix.
Blend your wet ingredients together as best possible. It won't completely mix together, but it will still work fine. While stiring, slowly add the wet ingredients to the mix. If it begins to foam, your adding the liquid too fast. Mix the reacting parts into a non reacting area and it should stop.
The consistency you are looking for is like wet sand.
You can add additional oil to the mix if too dry. The last batch I ended up adding an additional 1/2 cup of oil to get the right consitency.
Once your mixture is together, you have a pretty limited amount of time in which to get it into molds. You don't need to leave them in the mold for very long though, they can be removed almost immediately. Don't get discouraged if your first couple fall apart.
Dry them for approximately 24 hours to make sure they are hard.
They should last about 6 months.