Keep the original close
If you make videos, keep a copy of the finished export before you publish it. That source file gives you a reliable archive even if you later change a caption or remove a post.
Store originals in a folder you control, with a date and a short project name. A second backup on a separate drive or trusted cloud account can help protect work from device loss.
Use platform downloads when available
TikTok lets creators choose whether others can save a post. When a download option is available in the app, it is the clearest way to save a copy. If you use a third-party tool, use it only for content you own or have permission to save.
Keep useful context
Save the original project, exported video, and a small note with the post date and intended use. This makes it easier to find the right version later and respects the rights attached to the work.