Raele Altano shares phrases to redirect long-winded talkers without seeming rude. Try "I have something I've been meaning to tell you that you're going to love to hear" or "there's an idea I want to run by you" to invite them to listen while shifting the conversation focus.
There is a lot more I want to cover on long winded and short winded conversationalists, but here is a quick tip to get things started. If someone has been talking non stop for a while, going on and on about something, or sharing details that you don't really need to know, you can take the reins by saying something like I have something I've been meaning to tell you that you're going to love to hear, or there's an idea I want to run by you. What do you think about this? Specifically saying terms like by you or you'll love to hear invites the other person to listen and to collaborate in the conversation while still creating a segue and deviating from them a little bit. You're still making it partly about them while switching the focus over to you. I really love this tip and it works like a charm almost every time. I hope it's helpful.
