Stalk her social media accounts
"Women tweet, post, and pin the things they like, so check out your girlfriend's social media accounts for posts, pictures, and retweets that will give you clues into the styles she likes," Courtney and Shah say. She may have already pinned a dream engagement ring on her Pinterest's wedding board, or she probably has liked a few of her friends' rings on Instagram.
Ask one of her friends or family members for advice
If you feel you can trust someone to keep your secret under wraps, ask her sister, mom, or best friend for ring advice. "They may already have an idea of what she would like … or can get her to talk about a celebrity's engagement ring," Battad says. Her best friend will know how to get information out of her without it seeming fishy.
Capitalize on her obsession with celebrities
Does your lady spend Sunday night watching Keeping Up with the Kardashians? Does she crack up at Chrissy Teigen's tweets everyday? Whoever her celebrity girl crush is, pay attention! "Instead of rolling your eyes while she gossips about the Kardashians, listen in—you may get some great tips on the engagement ring styles she loves and hates," Courtney and Shah recommend. After all, who wouldn't want a cushion cut set between two diamond eternity bands like Chrissy Teigen's?
Get information with an Oscar-worthy performance
You can still ask about engagement ring styles in a non-direct way. "If someone you both know got engaged, mention the ring and see what she has to say about it … does she like it or does she prefer something else?" says Battad.
Find a reason to take her through the jewelry department
Ask your lady to go to the mall with you to pick out a new winter coat or shop for a birthday gift your sister. "Head to the mall or a big department store … just make sure your plans walk you right past the fine jewelry counter," Courtney and Shah say. Take note of what colors, diamond shapes, and styles she pays attention to.
Let her personality pick the shape
Is she in love with one-of-a-kind vintage furniture and all-things Brigitte Bardot? Or is she the type to fangirl over Rihanna's latest look? "More traditional ladies tend to choose round brilliant cuts, while those who fancy themselves trendsetters opt for less traditional fancy-shaped pieces like ovals, cushions, and even heart shaped diamonds," explain Courtney and Shah.