On Mondays, Wednesdays, and Fridays, Zac drops Alice off at school and Simon and I stay home together.

Once we get Zac and Alice out the door, I will finish feeding Simon if that didn't already get done. Then we head out for a walk for about an hour. I walk about 3.5 miles, during which time I either talk to Laura on the phone or listen to podcasts. When I'm not talking to Laura, I try to run a lot on the way back. Sometimes Simon stays awake and sometimes he sleeps.
When we get back home, I let him crawl around for a while. If he didn't nap on the stroller ride, he will usually nap soon after we get back.
When he naps, my rule for myself is that I read. I am currently reading
Middlemarch. It's one of those many classics that I haven't read, but have heard referenced, so I used a Barnes and Noble gift card to buy it online. The funny thing about buying a book online is that you don't have any idea how long it is. Sure, they list the number of pages in the details section, but I forgot to pay attention to that. It turns out my edition is 794 pages long. After a few days of reading, I'm only on page 147. This book is going to take me all summer. But, so far, it's good, with clever lines like "He took a wife, as we have seen, to adorn the remaining quadrant of his course, and be a little moon that would cause hardly a calculable perturbation" (88).
When Simon wakes up, I feed him lunch. I try to give him some finger food first, to have him keep practicing eating. It's still a work in progress, but I figure one way or another he'll eventually get the idea and actually like eating rather than taking one or two bites and then just squishing it, smacking it, or flinging it.
After lunch, I'll let him crawl around the house some more. He is pretty easy and will roam around by himself quite contentedly for long periods of time. Sometimes I carry him around and talk about things with him. Other times I sit with him so he can practice sitting, or I put him in the little rocking chair for a few minutes. While he is playing, I use the time to do any chores that need done, because I can keep an eye on him at the same time.
At some point, usually around 2 or 3, he'll go down for his second nap. After that I usually feed him again around 4. On average he eats 4-6 containers of food during the day, plus maybe two more for supper.
It's really fun just having a chance to pay more attention to him. And sometimes we just sit and click at each other for a few minutes.