Within object studio, any sensitive data should be stored as password data items. Any Application Modeller elements will be used to read or write data should have their data types changed from text to password.
Encryption should be turned on for your Work Queue - so any sensitive data held in the request cannot be retreived outside of a runtime production session
No client or sensitive data should ever be stored in the session log, loggin should be turned off for any process steps that might include the use of such data.
All of the above steps, and any other similar steps that are stipulated in your Security Policy (which you should have as part of your internal Robotic Operating Model) - should be checked as part of your UAT sign off, and your solution should also be periodically audited to ensure adherence.