Take the measurements of the space where you want to find the cubic inches. Take your measurements in inches, feet, or yards. Once you have determined the volume of your space you can use conversion factors to express it in the units you need, whether that be cubic inches, cubic feet or cubic yards. Draw a picture of your space on a piece of paper. If your space is not cubic or rectangular cubic in shape, be sure to measure the dimensions labeled. Divide the drawing into sections that are cubic or rectangular cubic in nature. Once you have found the volume of all the pieces they can be added together to find the total volume of space.Find the volume of each of the pieces by multiplying the height by the width and then mutilplying the product by the length. This will tell you the cubic inches in the volume. Find the number of cubic feet by dividing the number of cubic inches by 1,728. To find the number of cubic yards divide the number of cubic inches by 15,552.