How to set up a buy one, gift one promotion effectively?

[PB2030]

Hi - 

I am looking for any advice on how to properly set up a desired promotion. We would like to run a buy one, gift one concept. We are currently running email with Klayvio & SMS with Attentive.

The ideal flow would be: create discount code BOGO > customer enters it at check out and pays full price > automatically receives unique/ununique discount code via email or text that can be used by 1 email address (cannot be used by the one they used for check out). 

Any other suggestions for how to run the promo would be appreciated. 

Thanks - 

[PB2030]

Another option I thought of that would be ideal would be facilitating the gift so we direct ship to the customer receiving the gift. Any ideas on how that could work? Any option for second shipping address within Shopify? I know multiship exists but any other options?