I’m not one for lengthy tutorials if I can avoid it. I have followed many a tutorial in the past and slavishly followed every subtle colour change, every minor layer palette setting, etc, and spent hours striving to achieve the same result as the OP. I prefer quick results which can be customised to your heart’s content, to the nth degree… at your leisure.
I’ve pared the steps down to their bare minimum and still achieved a good looking reflective bubble. What do you think?
You can find my tutorial on how to create reflective bubbles in Photoshop here. Reflective PS Bubbles Tutorial