dehumidifier, try and focus on one room at a time at first, close all the doors and windows in that room and air vents and turn it on. And keep an eye of the water collected so you can empty it. Move room to room, I find closed rooms dry better than say the whole ground floor with all doors open, make sure there's no open water in the room like fish tank, water in plant pots, soaking dishes in the sink, toilet as the water will just be drawn from there, if you can't remove the open water source put some cling film over it.