I don’t think its Christ-like to tell a gay person they are sinning. Sure they are, but idolatry is also a sin and we all tend to be steeped in it. The point us are you offering them something better? And are you living an example that shows you yourself believe God is better than anything in this world? This is a kind of "if I were in your shoes I would be able to give my sexuality and everything that comes with it for God" moment, could we be honest? Can we also give the chance to fall in love, to have sex, and to marry for God alone? If we can't show them this resolve, this reality, this Joy we have, then we really don't have a right to tell them its a sin, since we literally are committing the exact same sin like the plank in our eye. Have we ourselves are willing to give up everything in our lives for God, or are we just playing double standard just because we are straight? So don't be like the guy who is telling someone to stop smoking cuz its bad for their health and yet goes gambling and drinking every night. Sincerity and love in your approach. Sincerity to show that you yourself am fighting and overcoming all you own sins because God is good, and love to show you truly want them to know God and know the Joy you have.