Here's some inspiration from Ikea for office/study/work spaces. http://www.ikea.com/us/en/catalog/categories/departments/workspaces/tools/workspaces_rooms_ideas/#/20123_wors03a_01 What is the size of the space you have to work with?

Something like this may work. Note the changed door positions so that anyone in the bedrooms can visit the bathroom without disturbing anyone else in the lounge !

Would you consider building a closet that would hold the platform on which your mattress would be placed? The outer side of the platform could have drawers or doors to the storage units under the platform. This kind of enclosure would work better for a twin bed than for a double, but it would provide a place where the bed can be concealed during the day time. Then, if you could allow a path between the bed enclosure and sofa, you could have the sofa face the dining table, or you could place the dining table at a right angle to the end of the sofa.

can you suggest how can designs my rooms