A.B.
I started putting my son on the potty at 16 months. After about 1 month of doing it several times a day (he did not object at all; he liked it. We read a lot of books!), he peed while he was on there. I got really excited, and he started doing it more and more until he did it every time. I put him on at logical times (upon wake up, after eating, before bath, before bed). He preferred the padded seat on top of the big toilet.
When they say you can't force it, they are right, but that doesn't mean you can't start trying early. If she doesn't mind sitting on the potty, just put her on there as much as you are willing, and eventually she will go. When she does, praise her, and she will do it more and more. My son was fully potty trained (days) by 21 months.
In my opinion, pull ups and training pants are a waste of time and money. Once you want her to make the connection to potty in the toilet all the time, GET RID of diapers and go straight to underpants. There will be accidents, but talk to her about them. Praise her every time you take her to the potty and her undies are dry. Expect to have to take her to the potty until she is at least two. She will start to tell you, but you can't rely on that.