2 criterias:
- Open standards in order to be able to open the document in 10-20 years (instead of WAV, use mp3). See list of open standards on Wikipedia.
You should think about what you want to get out of your certificates: one goal, one project (instead of one project for each project)
As an example:
Once you have a goal in mind, don't think too much: if you think something might be relevant, upload it.
The goal is to create the largest documentation base possible and there are no limits as to how many files can be added for a single certificate.
If the goal is to create proof of use of a trademark, don't limit yourself to the traditional evidence (emails, ...).
Questions? Feel free to reach out to [email protected] at anytime.