Dev, I am using my signature to earn BTC by doing other things now. But I can use my Twitter account to promote ShareCoin (I have 700+ crypto followers, still growing). If you can accept it we can have a deal.
I'm sorry but there is no plan for promoting on other social medias. The only way you can receive ShareCoin is using your signature.
You can edit your signature with an additional line mentioning ShareCoin. Only a word "ShareCoin" in your signature is good enough.