Act as a [native French speaker] with [5+ years of experience teaching conversational French]. Provide a detailed guide on how to learn [French slang and informal expressions] effectively. Include [specific resources like movies, podcasts, or books], [common pitfalls to avoid], and [practice techniques like role-playing or journaling]. Explain how to adapt these expressions for [different social contexts, such as casual vs. professional settings]. Offer [cultural insights] to help learners understand the nuances and avoid misunderstandings. Keep the tone engaging and practical, with examples like [popular slang phrases] and their meanings.