My Rosh Yeshiva instructed me with the following and it worked like a charm up until today: You date a girl in order to know each other. You talk, shmooze, laugh, and get comfortable. But that’s it. First, see if you’re compatible, and if this is who you’d like to spend your life with. Save the mushy stuff, and yes, even flower’s for AFTER the engagement. You don’t want to send any false messages, especially if she’s not your bashert! Flowers to a girl can be an agressive and powerful statement.
When engaged, the less you speak the better. He told me twice a week, (we ended up speaking a bit more :)), but I saw a sense of excitement build before each phonecall/visit. I sent gifts throughout the engagment, and flowers & a cards for Shabbos EACH WEEK. Again, no mushiness and no “I love you”s yet. That is for after marriage. Just HINT your love and that she’s special.
After marriage, go ALL OUT!! She’s your queen, your love, your life, the mother of your kids etc. The trick is, don’t stop!! So far, 10 years and 4 kids later, I can honestly say it just gets better and better.