1. Materials we need in this project.

2. Circuit diagram.

3. Some steps to make this circuit.

4. Connecting battery.

5. Test it.

Product list:

1 x BC547 transistor   https://www.utsource.net/itm/p/382309.html

1 x 220 ohm resistor   https://www.utsource.net/itm/p/8294786.html

1 x 100 ohm resistor   https://www.utsource.net/itm/p/8294784.html

More details, pls check the video on Youtube: