Talking about different topics during a conversation in French can really make it interesting. Here are some useful phrases you can use to help you switch topics smoothly:

1. To start a new topic:

   • "En parlant de..." (Speaking of...)
   • "À propos de..." (About...)

2. To connect ideas:

   • "Ça me fait penser à..." (That makes me think of...)
   • "D'ailleurs..." (By the way...)

3. To add something related:

   • "Et justement..." (And just so you know...)
   • "En fait..." (In fact...)

For instance, if you are talking about a movie, you can say, "En parlant de films, tu as vu les derniers?" (Speaking of movies, have you seen the latest ones?). Using these phrases can help your conversation flow better and keep it interesting!