In essence S1 can be replaced for any other circuit that will give a HIGH to the transistor. As it is a 240V Relay, you can connect AC appliances instead of just lighting LEDs, however please read the specs of your Relay carefully before using it to control any AC operated appliance.
Below you will find the circuit schematics and list of parts for this setup, and also a video showing step by step how to build the circuit on breadboard.
Components list:
T1 – BC547
R1 – 1KΩ
R2, R3 – 330Ω
L1, L2 – LEDs
6 Pin Relay
S1 - MOMON Button
Step by step video guide on how to build the circuit according to the schematic above: