“You can easily blink the LED with arduino or 555 timer. But You can make a blinking circuit without such ICs. This is an simple blinking figure made from discrete parts.
2sc1815 x 2 or any little NPN transistor
47μF x 2
4.7KΩ x 2 , 1KΩ x 1 , 100 Ω x 1 , 0 Ω x 1
CR2032 x 1
Red , Green or Yellow x 1