With most girls, it's best if they talk most of the time, but there are some girls where you should do most of the talking. If the girl lives a quite boring life and it's hard for you to get her to talk about herself, you can keep the conversation flirty and playful, or just talk about yourself. Flirty and playful is generally good for seduction. Talking about yourself with these girls is good, as this takes the pressure off of her and she can just enjoy and listen to your stories.
A good exercise to get good with these kinds of girls is to talk to a wall. Get comfortable talking to a wall for 10 min straight. I know it sounds a bit wired, but if you learn how to talk without any feedback at all, even the stillest most boring girl will seem to give you a lot to work with. This is only for this specific type of girl, for most girls it's better if they do most of the talking.