If you are watching any pornography at all, you need to stop immediately. 9 times out of 10 that is the core of the problem with any sins of lust in today's age. From personal experience, once I was able to cut that out (by the grace of God), the rest of my problems with lust began to dissipate over time.
I can't speak for same-sex attraction, but, as the above poster said, you just have to tackle this like any other serious problem with lust: prayer and custody of the eyes. Anytime you start getting perverse thoughts, pray and find something else to distract your mind. Don't dwell on it or act on it, just do what you can to respond to God's grace to fight it. Just take it day by day, you're going to fall and stumble, but the key is to get back up through prayer.
Remember, don't lose hope. You're not at all alone in this fight, you have the literal God of gods and Lord of lords looking over you with a hand extended to help, along with legions upon legions of angels and saints. I'll pray for you, friend.