Hi delima,
The important aspect is to check the good and bad sectors of the house. For example if you decide on a North sitting house then your Sheng Chi will be SE, Tien Yi will be East, Yen Nien will be South and Fu Wei will be North.
Mark it on the house plan and check whether the most common used area is in the 4 auspicious sectors. If you have health issue or you need flexible cash flow then you may want to select a room that is in the Tien Yi sector. You may want your maindoor or living room to be located in the Sheng Chi sector of the house. You may want your study room to be in the Fu Wei sector. For kitchen it is ok to be in the bad sector of the house but you must place your stove facing one of the best directions of either one of the couple (personally I will prefer to use the wife favorable direction, since stove represented her).
Now you can arrange your furniture to face your best 4 directions. For example you may place your bed pointing toward your Tien Yi, your sofa in a position that when you sit watching your TV you will be facing one of your 4 best directions and so on.
On the other hand the four worst sectors should be occupied by the bathroom, storeroom, service balcony and the least used area.
Hope the above can help you to understand better.
Bernard