How to assemble a Power Bank

As we know the power of banks is very useful for our gadgets. By using our power bank can recharge the battery gadget anywhere and anytime.
Currently power banks are found various brands on the market power.
But for people who hobby electronics, power bank can assemble themselves.
Here is a schematic circuit power bank 4200 mAh, with a 10 volt input and output 5 volts.

List of components required:

BT1 = Battery 7.4 Volt, 4200mAh
C2 = 1000uF / 16V
C3 = 470uF / 16V
R1 = 150 ohms
D1 = LED
U1 = LM 7805