Explanation

Ask them to rest and apply something cold to the injury – for example, frozen vegetables wrapped in a tea towel.

Applying something cold to the injury for up to 20 minutes will reduce external swelling and pain. 

Additional information:

Applying a cold compress, such as a bag of frozen vegetables, can help reduce swelling by constricting blood vessels and decreasing blood flow to the injured area.

This vasoconstriction can help limit inflammation and swelling.