Sunday mornings are a lie in for me (if I manage to stay in bed) whilst DH goes to play golf. I get up around 9am, strip the bed, put some laundry on, clean the kitchen & the lounge. By then, DH comes back so we get the DC to get dressed (they like to stay in PJs eating breakfast and watching TV on Sunday mornings) ready to take the dog for a walk.
We go for a good hour long walk usually, sometimes driving somewhere nice to do a new one, or down to the beach. When we get back I cook a roast dinner, or some variation if it's too hot. Today we're having slow roasted beef and yorkshire puddings, with roast potatoes, cauliflower cheese, braised red cabbage and honey roasted carrots. Whilst I'm cooking, DH cleans our bedroom, makes the bed and cleans the bathroom. DC do their own rooms.
After dinner we try to spend some time all together playing a board game or similar. Then baths/showers ready for the week.
I always have a bath on a Sunday night and take my iPad in to watch something in the bath. The thought of that hour alone keeps me sane all week!
Mostly, we don't "do" too much - we don't go to meet anyone, or do activities etc because we prefer to not be rushed. DH's golf is always early morning so he's back before lunch time for this reason also.