In order to connect to your instance, you will have first had to setup your cloud credentials on the computer you're connecting from.  See this knowledgebase article for details

In the management console, view instances and click on the ... under the Actions column.  Choose "connect to instance"

This window will display your instance name (in this example:  i-8e07e64c) and the name you gave it when creating the instance (in this example: test).  It describes how to setup your key file permissions so that you have access to it but no one else does.  Then it shows you the proper ssh command to connect to your instance with the instance IP address and your key name (substitute djm29.pem in this example for your key name).  

Please note that we have disabled root logins on CCR images and we recommend you leave it this way.  Each type of image has an account you can use that has elevated admin privileges using the 'sudo' command.  

The following are the account names for each type of instance (substitute 'root' in the command in the box above for the appropriate one for your instance):

Ubuntu instances, use the account name: ubuntu

CentOS instances, use the account name: centos

Debian instances, use the account name: debian

Please note that CCR only opens access to instances via the ssh service (port 22).  This access is also restricted to the UB and Roswell Park networks.  If you need additional access, please see this knowledgebase article