Redeem token with signature at MEW

[JakELips]

I got a mail with a "signature code" for my participation in a bounty campaign.
Can someone please explain how I can redeem the tokens with that "signature"?

I did not find an explanation in the help section of MEW.

[MadGamer]

Which campaign is that? MEW is just a wallet, the process of redeeming that code should be given by the campaign itself.