Often books on "rapport" suggest rapport-building techniques such as matching a person's voice tone and their pattern of speech, and mirror their gestures, etc.
The idea is that they will think : "You are like me, I like you more".
This can be effective in business situations, but not in attraction.
You can sometimes use this is she feels uncomfortable for some reason, and or at a later stage after you have attraction, but as a rule, not at the beginning of an interaction.
Much better is to understand when SHE is trying to get rapport with you.