At the ORCiD entry page, click on sign in. Instead of filling in your ORCID sign on and password, select access through your institution.

If you have already used a uark.edu email, the system should identify you as a member of the University of Arkansas.  If you have not, type the institutional name in the drop down box below (UAMS is another selection for the University of Arkansas).

You will be requested to sign in with your UA credentials:

When you have completed the sign-on process, ORCiD will seek for an appropriate ORCID id.  In the following case, I had used by campus account in my original ORCiD login and it immediately pulled up my account.