Set up a landing stage. (Clear room? / gazebo in the garden. Nowadays I always use our utility room floor - ex garage.)
Choose a room to sort and clear the floor. (Wouldn't bother sorting that stuff yet except for obvious rubbish.) Then work around the room, deciding / sorting / organising what stays in that room (cleaning happens later).
Move the stuff you know you want to keep, but not in that room, to your landing stage.
Review the stuff you moved off the floor - does it belong somewhere in the room you've just worked through (if so put it in its new home at that point, or does it go elsewhere? (I've bagged it up and placed it in the right area at this point,)
Generally try and think about where you do various activities and organise storage strategies for those areas as you go,
Put everything else in the skip. (When you've got a whole house to do you haven't got time to donate / recycle. - There are some skip companies that sort for you if that's easier to reconcile in your head.)
Move on to the next area.
Years ago I did bedrooms and bathrooms first, then kitchen and finally the lounge. I figured I'd sleep much better in a clear room and being able to get properly clean is a lovely feeling, but everyone's different. Kitchen has always been the centre of our houses and is in constant use, so made a big difference to how the day feels. Shed / garage / loft were last much much later.
Be prepared for your dh to find it really tough.