I found bluntness to be the best thing with my first. "I'm tired. I need a break to take care of myself. I will be gone from x time to y time on z day." Leave the house and get a pedicure, a haircut, a cup of coffee, whatever. DH did best when he didn't have me to fall back on.
This. DH, even before baby, did best with short and to the point. There came a point where, for a few months, I was going to be gone most of the week, so I needed some help with the household stuff. At first I laid out everything I usually do and asked what he'd be able to take on, since I shouldn't have to spend the only two days I had per week at home cleaning, grocery shopping, cooking, and doing laundry. He tried to talk his way out of helping out, not because he was a douche, but because he hates all of those chores. So finally I just said, "Ok, fine, how about this? I'm not going grocery shopping for the next x amount of weeks." I knew that was what he hated the most, so he offered to take on laundry duty instead, which I was fine with.
Is your H nervous around her or does he just think it's not dad's job to take part in this stuff? There are plenty of guys out there who think all the feedings, diaper changes, and other baby stuff is left to the mom. It isn't fair, but that's the way it is with some people. If he truly is nervous, then definitely do as PP suggested. If it's because he doesn't think it's his job, that's a much bigger problem that you need to address.