You are currently reviewing an older revision of this page.
When you drag an object with the RMB into an other object, automatically a pop-up appears, asking if you want to powerclip it 
Select it and it will be clipped .
Double click the powerclip with the LMB while holding down the Control key and the clipped object will become editable; you can reposition and / or resize it .
Click with the LMB outside of the powerclip while pressing the Control key and the edited powerclip will become of effect.