Research data can come to be reused long after a project has ended, for example to recreate results, use data for new analyses, or if someone wants to review published results after accusations of research misconduct. Even if there are no direct plans for further research on the material, it is important for you, as well as for potential reviewers, to be able to backtrack the research process. This means that you need to make sure that the documentation is so comprehensible and thorough that both you and others can understand the material, even after a long time.
Metadata (data on data, researcher, department, subject, area...) shall be registered at Swedish National Data Service (SND) by logging in to DORIS.
If you want to share your dataset through a repository you can use Zenodo (EU) but also different more subject specific repositories by using re3data.org.
Remember, you can always decide on license for usage of your open data, read more at Creative Commons (https://creativecommons.org/licenses/).