Though media based activism proposes positivity and effectiveness are possible in the realm of social/political movements on the platform of social media, slacktivism takes away all of that. Sharing a post cause your friends are doing it, or sharing it because you think you are helping is not enough to warrant the cheap satisfaction you seek for being helpful. And its not like I'm trying to say Don't participate in any media based activism without reading anything and everything about it before doing so, as doing so would not only be a large time commitment, what do I know; I'm just presenting my perspective and some facts to back that up. That being said, If you wish to be helpful, try to do more research into what you promote; look into the possible options of which you can actually assist the cause, and see whether or not posting about the cause is really going to do anything. Who knows, it may help the movement from collapsing altogether.
References:
(1). Agathangelou, A. (2011). Role of New media in the Arab Spring. In Arab revolutions and world transformations (Vol. 8, pp. 675-679).
(2). KONY 2012 CASE STUDY. (n.d.). Retrieved November 23, 2015, from http://www.kommunikationsforum.dk/log/multimedia/PDF og andre dokumenter/Specialer/Kony2012_Speciale.pdf