First, buy a PVC board with the size you need, write the advertising words you want on it, then drill all the small holes in the font to install LEDs, then buy the bright LEDs on the board in the electronic component market or Taobao, connect all the LEDs in series every four, and finally connect them in parallel (working voltage is 12V). According to the number of LEDs, choose 12V switching power supply. If you want to spend a little, you can use color led.