It'll also give off a gas, that's why you're outside. Don't breathe the fumes. When it is stirred, put the cap on the lye solution and bring it back inside. This will take two to three hours. You can make this lye solution the day before.
Lye solution is a very dangerous substance, it can cause death if ingested.
Make sure everyone in the house knows what it is and it is not to be touched. When the lye gets back down to room temperature, or if you made it yesterday and now today you're ready to start making your soap, start weighing out your fats. Here Stacy is weighing coconut oil and palm oil on our large scale. Stacy's molds are already prepared, so she can work in a hurry when the soap is ready to pour. Put the pot full of fats on the stove.