Well that is the way you do it unless you have an earlier version of IOS - which you do not bother to mention so we can only guess
You can delete photos from your photo stream the same way you delete other photos from your iOS device or Mac. Just select the photos you want to remove, and tap the trash can icon or click Delete. On your PC, select the photos you want to remove from your photo stream, right-click, and then select delete. When you delete a photo from Photo Stream on one device, iCloud will automatically delete it from the Photo Stream album or view on your other devices. Learn more about deleting photos.
Note: Deleting individual photos from Photo Stream is supported by iOS 5.1 or later, iPhoto 9.2.2 or later, Aperture 3.2.3 or later, and Apple TV Software Update 5.0 or later. You will need to manually delete photos you downloaded to iOS devices using iOS 5.0.1 or earlier after updating to iOS 5.1.