Once Logged into the Cloud Call Communicator Software and Opened You should see the below 

On the  top Menu please click on Contacts and Add Contacts (Single Contact)

Then Enter Display Name and First Name and Last Name add Phone Number and Click on Add 

To upload multiple contacts via  a CSV file into Cloud Call Communicator go to Contacts and Import Contacts 

Select the File Format CSV

Then Browser and  upload your CSV file with the file you would be able to find CSV template from your portal 

Then Click Next  and Import New Contacts and erase existing contacts or  you can add new contacts to exisiting contacts and then Click on Next 

Then Click on Finish