A resilient archive starts with the things you would genuinely miss. Do not begin by downloading everything. Begin with an inventory.
The KISS version
- Keep the original files where possible.
- Use common formats such as PDF, FLAC, MP4 and JPEG.
- Keep one working copy and at least one backup.
- Store a second backup somewhere different.
- Check that backups can actually be opened.
- Review the setup once or twice a year.
Preservation is not about collecting for its own sake. It is about keeping reasonable access to things you bought, created or were given permission to keep.