I read SWMNBN book recently and it was things like,
they can point to their body parts when named
can sit on potty for a few minutes at a time
...argh can't remember any more....
It suggested taking them with you to the toilet, and telling them what you're doing. ie, pulling down pants, having a wee, pulling up pants, washing/drying hands etc... to get them used to the procedure.
I thought it was quite a good read, and useful suggestions in it. (potty training in 1 week)