First, here is an example of how not to get your kid to do what you want:
Daddy: Molly, put your coat on please
Molly ignores him
Daddy: Molly if you don't put your coat on you'll get cold
Molly: No I won't….
Daddy: Your mummy gave you that coat for your birthday, and she would want you to put it on.
Molly: No, actually she gave it to me for Christmas.
This Daddy is giving different reasons for putting the coat on each time, hoping that one will stick. This is a gift for a contrary kid. She can pick just one flaw in your argument - in this case that the coat was a Christmas, not a birthday present- and start an argument.
The less ammunition the kid has, the less they can argue. Instead try this:
Daddy: Put you coat on please, it's cold
Daddy: Please put your coat on
Daddy: Coat on!
Molly: Ohhh, Ok…
Here, Daddy gave one solid reason, and then stuck to it. Then he used fewer and fewer words until the kid complied. He didn't need to get angry with the kid, just insistent, and there was nothing for her to argue about.