When I first started making soap, I was very exact with the temp of the oils and lye water. Now, not so much. I just throw it all together. Works for me, but I've been making soap for many years. Personally, I would not want to be carrying the lye water around. The less I have to handle it, the less chance of me accidentally dropping it. I mix mine in a container sitting in the kitchen sink, so if god forbid it spills, its going to spill in the sink. DO WEAR EYE PROTECTION DO WEAR A MASK and wear gloves. I remember once, I got lax on the protective equipment and breathed in the fumes a bit. I felt like I was in danger of going into a asthma attack ....and I dont even have asthma. It was scary.