How can I use my references again in the future?

All the references added to your profile can be reused for any future jobs you apply for.

To do that,  log in to Zinc here: https://zinc.work/sign-in,  and click on the profile tab.
On the top right corner you can set your profile to public by clicking on the “ Private “ button.

After your profile is set to public you can click on the “ Share profile “ button which will give you a link to your page.

Only the people with whom you share this link will be able to see your references.