Breakfast in the patio, a morning swim in the Cascais Bay, maybe buying some fish from the market just out of the ocean ... All walking distance.
What goes well with that lovely fish? Maybe some fresh white wine?
In the afternoon (after a quick nap of course) maybe a stroll in dowtown Cascais, an icecream at Santini, and how about a jogging towards Guincho beach?
In the evening, the Cascais Marina is calling for an exquisite dinner, overlooking the boats and the sea.
Sounds like a plan? ;)