Both of my girls started at 2yrs, although I did sit them on the potty "just for fun" from about 18mths.

A friend recommended thepottytrainer (google) so I checked out their method and it has worked for me wth both of my girls!

You could try sitting her on the potty now - but just for something fun like story time, so she becomes familiar with it.
But really, just start when youre comfortable