All electronic devices, such as cellphones and computers, contain Printed Circuit Boards or PCBs. A typical PCB has a large number of electronic components. Each of these components is connected to some other component through thin copper strips called traces. Together they make up the electronic circuitry designed to perform specific tasks. The size of a PCB depends on how many components it has, how densely it is populated and how many connectors there are on the board.
1 Open the circuit layout file in the PCB design software of your choice. This can generally be done by selecting "Open" in the "File" menu, browsing to the file and clicking "OK."
2 The layout screen will show an outline of the PCB with all the components clustered together on the left side. Move all components one by one inside the PCB outline and arrange them according to the circuit design. This can be done by dragging a component while keeping the left mouse button pressed. Releasing the mouse button at a location will move the component there. In most PCB design software, "Ctrl-R" can be pressed to rotate a component by 90 degrees. The best practice is to start with the component that has the largest number of connecting terminals and place it in the middle of the board. Then move the components that are directly connected to this component one by one and place them around it. Rotate the component if needed.
3 Increase or decrease the size of the PCB outline after all components have been placed inside. Leave at least half an inch of space around the edges of the circuit. In most PCB software, the size of the outline box can be changed by using the "Move" tool. This tool looks like a + sign. Click on it and then click on the line that needs to be moved. Drag the line outward or inward to increase or decrease the size. Press "ESC" when the line has been moved to the intended position. Repeat this process to adjust the size of the board.
4 Measure the size of the outline box. In most PCB software, the size of a line can be determined simply by left-clicking on the line. The size of the line appears in a bar above the layout. Multiply the sizes of a horizontal and vertical line of the box together to get the size of the board.