How do I .... grant access permissions for SSIS to users?

 SSIS access permissions are managed via Component Services. It is the DCOM object named MSDTSServer. Here are the steps to follow. 

1. Component Services -> Computers -> My Computer -> DCOM Config -> MSDTSServer
2. Right click on MSDTSServer
3. Click properties
4. Click on the Security tab
5. Select Customize and add the users/groups to the Launch/Activation and Access tabs accordingly
6. Add the user to the local Distributed COM Users group
7. Restart the SSIS service
8. Methos -2 
9. 1. Right-click My Computer>Manage>Configuration>Local Users & Groups
10. 2. Look for the Distributed COM Users group and add the account.