From r/lifeprotips:

"LPT: When someone you love is going on and on about a topic you struggle to care about, shift your attention to them and their excitement about the topic as they share. Guaranteed you'll be more engaged and you'll both enjoy the interaction more than had you just nodded along feigning interest."

Obviously replace "someone you love" with "your date", but the rest is extremely relevant.

This should be common sense, but isn't. Lots of guys wonder why their dates don't go anywhere, this is one of the reasons why.

Find out what her passions are and inquire deeper about them. Show interest in the things she's interested in and get her to open up about herself and the things she loves. Women are emotional and love talking about their passions so they will naturally feel good when doing so, subconsciously enhancing how they feel with you and attaching that emotion to you as a result as well.

This is "chemistry" in a nutshell.