Multi-posting is the only way to ensure long-term stability. If one platform bans you, you have two others.
Dealing with Watermarks
Never post a video with a TikTok watermark on YouTube. It's an instant "Shadowban" for that piece of content.
Platform-Specific Hooks
Sometimes a hook that works on TikTok fails on Instagram. Experiment with different titles and captions for each platform.
Scheduling Tools
Use automation to schedule your posts so you aren't tied to your phone all day.