My wife wanted a marquis her whole life until we went in a jewelry shop and she tried it on. Then she wasn't impressed. But it gave me a rough idea of what she wanted, and better yet, didn't want. Somehow I managed to knock the ring out the park, Took like 4 hours picking the right band and diamond though. I went on my own. If there are clues or talk about marriage, plant into her head the idea of taking you to look for rings with her but don't buy with her there, just go to do it as something to fill an afternoon. That's what happened with me and I felt hyper uncomfortable when I was in the shop with her. She had no idea but it actually gave me all I needed to work it out myself. And it still was a total surprise when I did propose. Good luck