This is a basic exercise for the noobs in arduino.
I enjoy programming and i think that mi code could be interesting for someone. In my review if you want to learn to programming you shouldn´t copy the code at all in the first time, you should try your code using this as reference or solution only if you feel that you can't.
My Simon only works with three colours because i haven't jumpers for four.
I program it to have speaker but i forget it in home, if it sound weird is because i never try the sound but it should work.
Well, I will start to tell you how i do it
P.D.: Sorry for my english, i´m spanish and this is difficult for me.
Step 1: Hadware
For this proyect we will need:
3 1M Ohm resistor
1 220 Ohm resistor
1 led yellow
1 led red
1 led green
1 led blue (i use it as a brand to start the game)
1 Arduino ( i use Arduino Mega)
you could conect like the photo