Like what the rest having mentioned, being patient is key. If your child is resistant, try taking a break from the training and resuming after a couple of weeks.
I think if the reason that you are worried is because of her starting nursery, you can relax a little. Going to nursery may actually help as she will get to see her peers going to the toilet on their own. She may learn from them and would want to do so herself too.
Just for your reference, here is an article on when to start potty training: http://sg.theasianparent.com/when-should-i-begin-potty-training-my-toddler/
And here's one with some useful tips on how to go about doing it:
http://www.parents.com/toddlers-preschoolers/potty-training/tips/potty-training-tips/#page=1
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