What I've done/am doing:
We have enough food, prescription medicine, cat litter, supplies, etc that if we were asked not to leave our house for 2-4 weeks, we would not need to break quarantine. We generally always keep 1-3 weeks at a minimum, so this has mostly just consisted of getting another package of whatever when the current one is about half empty, instead of "we're out."
Washing my hands more. I'd love to say I've always been a great hand washer, but let's be real. I washed after using the restroom and cleaning the litterbox, and that's about it. Now, I'm additionally washing when I get to work, when I get home, and before I eat or prepare food.
Utilizing online order/curbside pickup for groceries. I halfheartedly did this anyway, but fewer people in stores touching things means fewer points of transmission.
Canceled a trip to a conference next week. It wasn't necessary to go, and again, I think the fewer people out traveling from place to place, the better right now.
I expect it won't be long till my company asks us to work from home. My guess is that will come in another 2-3 weeks.