Soap making is very easy. I use the process referred to as melt and pour. You start out by melting glycerine (You can readily find this in any craft section now).
Follow the directions on the package. I cut the glycerine into cubes, placing it in the mold to estimate how much soap I need. You can melt the soap in a microwave or on the stovetop in a double boiler. There are also soap "melters" available in stores, which basically look like crock pots.
I find it easiest to melt soap in a microwave safe measuring cup in the microwave. The cup makes it easier for pouring into molds. If you do melt it in the microwave, cover it with plastic wrap first to avoid evaporation. Once the soap is melted, add any scent or color desired and pour into mold.
You can use essential oils or scents made specifically for soap (scented fragrances). For coloring soap you can use dyes made specifically for soap or food coloring. Food coloring is safe to use in soap, it won't dye your skin or towels or anything else. However, food coloring tends not to hold it's color as well as soap dyes. It may fade or change color after time.
As soon as you pour the soap into molds spray the top with some rubbing alcohol in a spray bottle to get rid of air bubbles. Spraying with rubbing alcohol between layers when making layered soap is also a good idea. Once in molds allow your soap at least a couple of hours to harden (larger molds may need to set as long as overnight).
Have fun with your soap, try using things not meant as soap molds to make soap in. Just keep in mind you do have to unmold it. I've made soap for children in popsicle molds, replacing the plastic handle with a regular popsicle stick. I've used a Pringles can to make a round loaf soap, simply peeling the can away when I was ready to unmold it.
There are many supplies and even kits available in craft stores now for soap making. Everything from simple melt and pour techniques, to more complex things. There are lots of books and websites on the subject too. Here are a couple of sites I've found interesting.
Learn Soap Making Techniques
Recipes For Soap, Lip Balm And More
Soap Making: