To design an interior of a project the first thing to do is visit the project. By visiting the site , we have to note down all the measurements of the site such as floor area, every wall length and height, bathroom size etc. these measurements will help to make the design properly. If the measurements were wrong then many amounts of materials should be wasted.  After getting the measurements then a cad drawing of the site should be made. Then we have to think about what design and what elements can be used in that design. We have to make 2d and 3d drawings for every part of the site to show our client that he will make changes of his choice. Then finally we have to make a cost estimation for the project.