As a stay-at-home mom, I've been asked that question a few times. Mostly, it's been with genuine curiosity. Here's my answer, as told to my Grampa last weekend.
"We wake up, and I change the boys' diapers. Then I dress them. Next, I nurse them. And I feed them. On a good day I get dressed and fed too. Then we play for awhile. I spend the rest of the day trying to get them to sleep."
That's the simple version, but that's it in a nutshell. It's a rare and special day that I get them both napping at the same time.
Often one will nap while the other plays and snuggles with me, then they switch off. I actually really enjoy those days, especially the one-on-one time, unless I'm exhausted and yearning for sleep myself. Some days the babies fight sleep with the strength and intensity of samurai warriors. On those days we pile into the car and drive around until they drift off, then we go to Nana's house where I attempt to carry them inside oh so slowly, oh so carefully. Usually they wake up, so we play at Nana's.
I am alone with two nine-month-olds for much of every day, but the amazing, wonderful, comforting fact of life is that I'm not really alone in this. Hubby comes home every day after work, ready to scoop up his boys and give me time to shower, or sleep, or read. And Nana comes home, delighted to see all three of us at her house, and sings and plays with the babies while I read the newspaper or grab a real lunch. And I can always call my sister, my brother-in-law, my brother, or my dad if I need them.
So what do I do all day? I raise my babies, surrounded and supported by my family. Best. Job. Ever.