Nobody 'just' knows stuff, we've all had to learn one way or another . Mostly by asking other people, like you do now.
Although I used to work with LaDoll clay, I've recently turned to Super Sculpey. Both have their pro's and con's. I love that you're able to work on a SS sculpt indefinitely, until the time that you bake it. LaDoll clay will start to dry pretty fast. Another positive thing about Super Sculpey is that you can use big slabs of clay. With LaDoll, because it cracks easily, it's best to work in layers. Which means that LaDoll is a bit slower in use at first.
The main downside is that Super Sculpey is quite brittle. It's easy for joints to break, fingers to snap and although it's hardy, it isn't flexible in the least (which means that it's easy to break a SS piece by dropping it). LaDoll is much more reliable in that part. For instance, I've had to resculpt one leg in Super Sculpey FOUR times, because it kept on breaking. With LaDoll this wouldn't have happened and it's easier to repair breakage - you just use a little clay to 'glue' the pieces together. I've had LaDoll pieces take quite a tumble and the only thing wrong with it afterwards was a little dent. I don't trust Super Sculpey to do the same.
But even with the downsides, Super Sculpey works a lot faster in my experience. Which is why I'm quite content with it now.
As for tools: Well, when I first started out, the only thing I had was one spatula and an exacto-knife. Other tools came when I felt I was missing something. I really depends on what your sculpting style is, what tools are useful to you. So my advice is to first get yourself a good spatula with a pointy side and a flat side and buy other stuff when you need to.
Things I'm currently using: A spatula Two exacto-knives with different size blades Thin wire to cut clay with. 2 different silicone brushes 6 different chizels
I'm a carver, so I need the two exacto-knives and the chizels to work the clay, but if you are a modeler, you might want to invest in more silicone brushes instead.
Don't buy tools in a set. I did so when I bought my chizels, but this was because they contained the shapes I needed and they were on sale. Usually, it's much better to buy tools one at a time, because otherwise you'll end up with a lot of stuff you never use.
For mor infomation on doll making, please check out www.denofangels.com/joints. This forum is very helpful and has tons of info anyone could use .
No, I'm very bad at sewing anything. I keep in mind what the general size of these dolls are - mostly the neck circumference, the size of the feet and the height - but then I'll just go looking for cothes that fit. There are so many BJD's out there, all with different measurements. As long as you don't go completely overboard with your design, there should Always be some outfits your doll could wear.