How to migrate data, dashboards, and apps from Splunk Enterprise installed on-premises to Splunk Cloud?
Migrating on-prem data: Speak to your Splunk rep.
Anything requiring CLI access: Issue a jira ticket to the cloud ops team.
Migrating apps: assuming the app is a self-made one, it needs to be vetted by the cloud team.
for more information, see here: http://docs.splunk.com/Documentation/SplunkCloud/latest/User/GetSplunkCloudapps