1. Copy some text into the clipboard (in case it's completely cleared, which would be rare, but some privacy/antivirus apps do this)
2. Open any app where you enter text (phone text messages, Facebook, whatever), and click into the text entry window
3. Manually long press that window
4. You should get a two part pop-up icon with Paste and Clipboard options.
5. Select Clipboard.
6. From the resulting window you can select recent clipped/copied content or Delete All clip content