Here are some recommended precautions when using public cloud storage services for personal files:

1. Ensure the service provider has the latest security updates and measures in place.
2. Encrypt sensitive and personal data before uploading to the cloud.
3. Change passwords on a regular basis.
4. Be aware of third-party applications and services that have access to your data.
5. Pay attention to the service provider’s terms of service.
6. Backup important data locally.
7. Review sharing and privacy settings.