Lye: You DO have to work with lye to make soap. You HAVE to wear glasses to prevent the lye from getting into your eyes. I do not wear gloves or an apron.
If the lye gets on your skin, you can wash it off. Lye feels very slippery to the skin. You need to flush the area with water while you rub the "slippery" away. Then I wash a bit beyond that to ensure I have all of it off of me. When lye gets on my skin, I first feel an itch. If it is on my skin for too long, it starts to burn.
Is it hard? Making the soap is not hard at all if you can follow directions, have accurate equipment (scales and thermometers) and pay attention to details. Soap ingredients and temperature have to be precise.
How to make it: There is one main book I recommend reading when learning how to make milk based soaps. This book will teach you all you need to know and has several recipes to try.
Milk-Based Soaps: Making Natural, Skin-Nourishing Soap
This is for water based soaps, but has tips and recipes to gather ideas from when experimenting.
Soapmaker's Companion: A Comprehensive Guide with Recipes, Techniques & Know-How (Natural Body Series - The Natural Way to Enhance Your Life)
Other Milk: I have not tried other milk.
Canned Milk: While I have used canned goat's milk for my personal use face cream, I do not use it in milk making. It would not be cost effective. I am not sure how it would affect the process. I know some ladies have canned milk from their goats and it has not worked well in the recipes.
There are many, many women online making goat's milk soap. Some of them have wonderful recipes and pages set up to help the beginner.
For general soapmaking (not milk specific): Kathy Miller's page is excellent!
Skin conditions I personally know it has helped: eczema, dry skin, those scaly, bumpy arms, psoriasis, poison ivy/sumac/oak, etc.
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