I hear ya man, I have three dogs that take way too much of my time up so I can image kids are a lot harder. I've had that kit before and it sucks to be honest. It's overpriced and the rubber molds don't really hold up over time and the resin cures way too fast. The only good thing out of it is that blue clay. If you are familiar with the customizer Ole Jade Jaw, he just spent an hour on the phone teaching me how to cast and I have it down pretty good now. Here is what I do:
Drill a really tiny hole in the top of the head, figures with hair seem to be the best because I can hide the hole in between strands of hair.
I use Vallejo paint so I have a ton of caps laying around, so I drill a hole through the top to get the end of a toothpick through it. I superglue the toothpick end into the hole I drilled from the last step
I bought the mouthwash paper cups and put clay down and then the upside down head into the clay.
Pour my mold in, let it dry over night.
Cut the paper cup and then do a zig zag cut into the side of the mold about half way down and pop the head out.
I put non fragrance (apparently there is a bad chemical reaction that occurs with fragrance brands) talcum powder in the mold, shake it, and blow out the excess.
When you pour your resin in, squeeze the sides of the mold. By using the toothpick to make the tiny funnel, it creates a vacuum that sucks the resin down into the mold.
Mold I use is OOMOO 30
http://www.smooth-on.com/Silicone-Rubbe ... index.htmland the Resin is Smooth-Cast 326
http://www.smooth-on.com/index.php?cPath=1206Some things to remember:
The ten minute cure time can be a killer, that is why I go with the 326 (60 minute cure time) because it starts to turn into gel within minutes and that doesn't allow to get into the mold fully.
The stuff I recommended is not kidding about the working temps (73 degrees I think) because I work in a cold basement and it extends the cure time
Stuff like holdsters, Batman heads, and women with long hair OR if you want the Smooth-cast to harden crystal clear, you need a pressure pot to suck all the bubbles out. If you are good with putting stuff together, you can make a pot for around $200 or if you are a money bags, you can buy one for $700 or so.
Smooth-on also makes a pigment that works with the smooth-cast if you want to make colored casts.
Good luck and let me know if you have any questions.