You can link profiles on the 'Social Profiles’ section as normal.
If you don’t have any slots left:
Then you can add a new social profile or activate, upgrade or migrate one of your existing handles as explained above.
NB: As of the 25th September 2018, all new Instagram profiles added to Iconosquare must be Business Profiles. This includes free trials and adding new profiles to your paid plan. Further to this, as of the 23rd October, use of Iconosquare will be entirely restricted to Business Profiles. So if you have a personal account that you'd like to convert to a Business Profile so that you can add it to Iconosquare, you can learn how to do that here!