My therapist often says that I should stop trying to think of the best way to say it before I say it. She said that I should just say whatever is in my mind right at the moment and stop trying to find the best wording so it sounds "right" for her, whether that is me trying to downplay it, or me trying make it sound least unpleasant to her, or me trying to make it sound least embarrassing for her, whatever it may be, I should ignore that urge, and just say what is in my mind right at the moment. It's almost like I'm blurting out what's on my mind, in a sense. It's hard but when I notice I'm holding back on telling her something because I am embarrassed, I just take a deep breath and then just say it out loud right there. Then once I get that first bit out, it gets the ball rolling, and I can it becomes a bit easier to talk, though it's still a challenge. Plus, my therapist can also help encourage me, or nudge me along once that first part comes out.
Hope that helps.