Install SigningHub for Word from your on premises store
SigningHub for Word can either be installed from your on premises store or from the Office store.
To install the SigningHub add-in from your on premises store, the Office manifest file should exist in your app catalog site, see details. This installation method is useful when direct access to the Office store is disabled in your organisation.
Install SigningHub for Word from your on premises store
Log into your Office 365 account.
Click the "Word" option.
Microsoft Word Online will be launched.
Open Word Online, click the "INSERT" menu and then click the "Office Add-ins" option. A dialog will appear, click the “MY ORGANISATION” option.
The SigningHub for Work add-in will appear in the dialog. Select it and click the "Add" button.
This will put the "SigningHub" option under the HOME menu.
Click the "SigningHub" option to launch the SigningHub for Word add-in at the right panel of Word Online. Login with your SigningHub account credentials and start sharing your documents, see details.