What is the best way of trading game keys?

[Ad Hominem]

I have a bunch of game keys I have accumulated over the years from Humble Bundle and I would like to start getting rid of them instead of letting them collect digital dust. Aside from just giving them away, what is the best method to go about trading game keys?

I assume that simply sending the game key in plain text is a bad idea because it would be too easy to scam/be scammed, but I'm not sure what else I can do. I don't usually trade anything so I'm not familiar with the process or the rules.

[Spawn of Totoro]

With people you know and in person.

Anywhere else is open to one or the other getting scammed.

I suggest giving away keys to friend and such, for their birthdays or other holidays.

[Aachen]

Trading game keys is not supported by Steam, so it’d be either the aforementioned giveaway, at-your-own-risk, or using some other service where you’d naturally be better off with your inquiry.

[Ad Hominem]

OK thanks, looks like random giveaway it is. I've pretty much given my friends the first look to take what they want but I still have a sizable list with a few high profile games.

[Silicon Vampire]

Be aware some of those keys may have had expiration dates...