Cover your tracks
Definition 1 of 2
Pro Tip 1/3Literal Origin
Originally referred to hiding footprints; now means hiding any evidence. 
After the party, they covered their tracks by cleaning up before the parents arrived.
Pro Tip 2/3Metaphorical Use
Often used metaphorically for hiding digital or indirect evidence. 
She covered her tracks by deleting her emails and internet history.
Pro Tip 3/3Negative Connotation
Usually implies wrongdoing or guilt; not often used for innocent situations. 
To avoid suspicion, the corrupt official covered his tracks with fake documents.