Introduction: PIR Motion Sensor Alarm
The thing you need to build this project is four wires,bread board,arduino,Alarm,Laptop. First thing you do is connect all the wires to arduino and bread board and the alarm then go to the arduino software on laptop and upload the code.
Code is here- https://raw.githubusercontent.com/jedgarpark/Make_PIR_Sensor/master/MAKE_PIR_Sensor.pde.
And then everything should work after you upload the code.