Open module My Company
On the left you will find various module. Here you will see the module "My Company". Clicking on this will give you several options under this button.
Open contacts
In the overview that is located under "My Company", you will find the button "Contacts". Clicking on this will open the screen with an overview of all your contacts.

Add partner
You can add your desired partner by clicking on the "Add" button. This green button is located on the right, at the level of the supplier's name in the "Actions" column.
Next you will get a screen where you have to enter your customer number of the partner in question. If you have done this click on next.
Once you have clicked on "next" a request will be made to create a link. For some suppliers, it may take several days to complete the activation.