Imagine yourself in this position:
You're at a party, and someone asks you to sit down at the piano, puts a chord sheet in front of you, and says "play this."
What would you do?
This is exactly what happened to a student of mine the other day and I'm happy to report that she had the ability and confidence to not only play something that sounded good, but that she enjoyed the experience!
That's the first stage: learning how to play from chords and enjoy the experience. Once you begin to learn this skill, you'll find that it's easy once you get the hang of it.
The next stage is to keep experimenting and trying out new things. The more you become curious about what's possible, the more fun it becomes. As one example, if you played the melody with your LH, what would you play with your RH?
The "method" is to simply let go of your inhibitions, become a kid again, and "dive in." Learn your chords, and then learn some simple ways to apply them to chord sheets. Once you begin, you'll have so much fun you'll never look back.
Enjoy the journey, and "let the music flow!"