Telegram, Discord, X (formerly Twitter), and Reddit remain the most powerful platforms for ICO marketing. Telegram and Discord foster real-time engagement, X is crucial for trending hashtags and updates, while Reddit allows deep discussions and AMA sessions. Medium is ideal for thought-leadership content like whitepaper summaries and technical articles. LinkedIn works well for professional credibility and attracting serious investors. Paid campaigns can leverage crypto-specific ad networks like Coinzilla, Cointraffic, or blockchain news outlets for visibility. However, platform choice depends on your target audience: retail investors are found in Telegram and Reddit, while institutional interest grows on LinkedIn and niche crypto forums.