In this tutorial I will show you how to blink 1-12 leds. I have designed the code so that you can insert 1-12 leds but you can edit it so that you can insert 13 or more.

Step 1: Materials

For this project you will need:
Wires
Arduino board
1-12 leds (im using 10)
usb adapter
solderless breadboard

Step 2: Inserting Leds

Take your leds and put them in a row on the breadboard. Make sure you know which side of the led is positive and which side is negative. I like to point the positive side of the led towards the right. Also, keep a one hole spacing in between each led

Step 3:

Now, plug in a medium sized wire into the first hole on the negative row on the top of the breadboard.

Step 4:

Now insert wires in front of every positive side of each led.

Step 5:

Now insert wires in the negative row that you put the medium wire in. now plug those wires into the negative sides of the leds.

Step 6:

Now we have to plug the wires in. Position the arduino board so that you can plug the wires in from arduino pin 1 to arduino pin 12 but it doesnt matter what pin you go up to.

Step 7:

Now plug the negative wire into GND.

Step 8: CODE

int ledPins[] = {
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 };       // an array of pin numbers to which LEDs are attached
int pinCount = 9;

void setup (){
pinMode (1, OUTPUT); // different led patterns
pinMode (2, OUTPUT);
pinMode (3, OUTPUT);
pinMode (4, OUTPUT);
pinMode (5, OUTPUT);
pinMode (6, OUTPUT);
pinMode (8, OUTPUT);
pinMode (7, OUTPUT);
pinMode (9, OUTPUT);
pinMode (10, OUTPUT);
pinMode (11, OUTPUT);
pinMode (12, OUTPUT);
}

void loop (){
digitalWrite (1, LOW);
delay (60);
digitalWrite (2, LOW);
delay (59);
digitalWrite (3, LOW);
delay (58);
digitalWrite (4, LOW);
delay (57);
digitalWrite (5, LOW);
delay (56);
digitalWrite (6, LOW);
delay (55);
digitalWrite (7, LOW);
delay (54);
digitalWrite (8, LOW);
delay (53);
digitalWrite (9, LOW);
delay (52);
digitalWrite (10, LOW);
delay (51);
digitalWrite (11, LOW);
delay (50);
digitalWrite (12, LOW);
delay (49);
digitalWrite (1, HIGH);
delay (48);
digitalWrite (2, HIGH);
delay (47);
digitalWrite (3, HIGH);
delay (46);
digitalWrite (4, HIGH);
delay (45);
digitalWrite (5, HIGH);
delay (44);
digitalWrite (6, HIGH);
delay (43);
digitalWrite (7, HIGH);
delay (42);
digitalWrite (8, HIGH);
delay (41);
digitalWrite (9, HIGH);
delay (40);
digitalWrite (10, HIGH);
delay (39);
digitalWrite (11, HIGH);
delay (38);
digitalWrite (12, HIGH);

delay (37);
digitalWrite (12, LOW);
delay (60);
digitalWrite (11, LOW);
delay (59);
digitalWrite (10, LOW);
delay (58);
digitalWrite (9, LOW);
delay (57);
digitalWrite (8, LOW);
delay (56);
digitalWrite (7, LOW);
delay (55);
digitalWrite (6, LOW);
delay (54);
digitalWrite (5, LOW);
delay (53);
digitalWrite (4, LOW);
delay (52);
digitalWrite (3, LOW);
delay (51);
digitalWrite (2, LOW);
delay (50);
digitalWrite (1, LOW);
delay (49);
digitalWrite (12, HIGH);
delay (48);
digitalWrite (11, HIGH);
delay (47);
digitalWrite (10, HIGH);
delay (46);
digitalWrite (9, HIGH);
delay (45);
digitalWrite (8, HIGH);
delay (44);
digitalWrite (7, HIGH);
delay (43);
digitalWrite (6, HIGH);
delay (42);
digitalWrite (5, HIGH);
delay (41);
digitalWrite (4, HIGH);
delay (40);
digitalWrite (3, HIGH);
delay (39);
digitalWrite (2, HIGH);
delay (38);
digitalWrite (1, HIGH);
delay (37);

digitalWrite (12, HIGH);
delay (60);
digitalWrite (11, HIGH);
delay (59);
digitalWrite (10, HIGH);
delay (58);
digitalWrite (9, HIGH);
delay (57);
digitalWrite (8, HIGH);
delay (56);
digitalWrite (7, HIGH);
delay (55);
digitalWrite (6, HIGH);
delay (54);
digitalWrite (5, HIGH);
delay (53);
digitalWrite (4, HIGH);
delay (52);
digitalWrite (3, HIGH);
delay (51);
digitalWrite (2, HIGH);
delay (50);
digitalWrite (1, HIGH);
delay (49);
digitalWrite (12, LOW);
delay (48);
digitalWrite (11, LOW);
delay (47);
digitalWrite (10, LOW);
delay (46);
digitalWrite (9, LOW);
delay (45);
digitalWrite (8, LOW);
delay (44);
digitalWrite (7, LOW);
delay (43);
digitalWrite (6, LOW);
delay (42);
digitalWrite (5, LOW);
delay (41);
digitalWrite (4, LOW);
delay (40);
digitalWrite (3, LOW);
delay (39);
digitalWrite (2, LOW);
delay (38);
digitalWrite (1, LOW);
delay (37);

digitalWrite (12, HIGH);
delay (60);
digitalWrite (10, HIGH);
delay (59);
digitalWrite (8, HIGH);
delay (58);
digitalWrite (6, HIGH);
delay (57);
digitalWrite (4, HIGH);
delay (56);
digitalWrite (2, HIGH);
delay (55);
digitalWrite (1, HIGH);
delay (54);
digitalWrite (3, HIGH);
delay (53);
digitalWrite (5, HIGH);
delay (52);
digitalWrite (7, HIGH);
delay (51);
digitalWrite (9, HIGH);
delay (50);
digitalWrite (11, HIGH);
delay (49);
digitalWrite (11, LOW);
delay (48);
digitalWrite (9, LOW);
delay (47);
digitalWrite (7, LOW);
delay (46);
digitalWrite (5, LOW);
delay (45);
digitalWrite (3, LOW);
delay (44);
digitalWrite (1, LOW);
delay (43);
digitalWrite (2, LOW);
delay (42);
digitalWrite (4, LOW);
delay (41);
digitalWrite (6, LOW);
delay (40);
digitalWrite (8, LOW);
delay (39);
digitalWrite (10, LOW);
delay (38);
digitalWrite (12, LOW);
delay (37);

digitalWrite (2, HIGH);
delay (60);
digitalWrite (4, HIGH);
delay (59);
digitalWrite (6, HIGH);
delay (58);
digitalWrite (8, HIGH);
delay (57);
digitalWrite (10, HIGH);
delay (56);
digitalWrite (12, HIGH);
delay (55);
digitalWrite (1, HIGH);
delay (54);
digitalWrite (3, HIGH);
delay (53);
digitalWrite (5, HIGH);
delay (52);
digitalWrite (7, HIGH);
delay (51);
digitalWrite (9, HIGH);
delay (50);
digitalWrite (11, HIGH);
delay (49);
digitalWrite (1, LOW);
delay (48);
digitalWrite (3, LOW);
delay (47);
digitalWrite (5, LOW);
delay (46);
digitalWrite (7, LOW);
delay (45);
digitalWrite (9, LOW);
delay (44);
digitalWrite (11, LOW);
delay (43);
digitalWrite (2, LOW);
delay (42);
digitalWrite (4, LOW);
delay (41);
digitalWrite (6, LOW);
delay (40);
digitalWrite (8, LOW);
delay (39);
digitalWrite (10, LOW);
delay (38);
digitalWrite (12, LOW);
delay (37);

digitalWrite (12, LOW);
delay (60);
digitalWrite (11, HIGH);
delay (59);
digitalWrite (10, LOW);
delay (58);
digitalWrite (9, HIGH);
delay (57);
digitalWrite (8, LOW);
delay (56);
digitalWrite (7, HIGH);
delay (55);
digitalWrite (6, LOW);
delay (54);
digitalWrite (5, HIGH);
delay (53);
digitalWrite (4, LOW);
delay (52);
digitalWrite (3, HIGH);
delay (51);
digitalWrite (2, LOW);
delay (50);
digitalWrite (1, HIGH);
delay (49);
digitalWrite (12, LOW);
delay (48);
digitalWrite (11, HIGH);
delay (47);
digitalWrite (10, LOW);
delay (46);
digitalWrite (9, HIGH);
delay (45);
digitalWrite (8, LOW);
delay (44);
digitalWrite (7, HIGH);
delay (43);
digitalWrite (6, LOW);
delay (42);
digitalWrite (5, HIGH);
delay (41);
digitalWrite (4, LOW);
delay (40);
digitalWrite (3, HIGH);
delay (39);
digitalWrite (2, LOW);
delay (38);
digitalWrite (1, HIGH);
delay (37);

digitalWrite (12, HIGH);
delay (60);
digitalWrite (11, LOW);
delay (59);
digitalWrite (10, HIGH);
delay (58);
digitalWrite (9, LOW);
delay (57);
digitalWrite (8, HIGH);
delay (56);
digitalWrite (7, LOW);
delay (55);
digitalWrite (6, HIGH);
delay (54);
digitalWrite (5, LOW);
delay (53);
digitalWrite (4, HIGH);
delay (52);
digitalWrite (3, LOW);
delay (51);
digitalWrite (2, HIGH);
delay (50);
digitalWrite (1, LOW);
delay (49);
digitalWrite (12, HIGH);
delay (48);
digitalWrite (11, LOW);
delay (47);
digitalWrite (10, HIGH);
delay (46);
digitalWrite (9, LOW);
delay (45);
digitalWrite (8, HIGH);
delay (44);
digitalWrite (7, LOW);
delay (43);
digitalWrite (6, HIGH);
delay (42);
digitalWrite (5, LOW);
delay (41);
digitalWrite (4, HIGH);
delay (40);
digitalWrite (3, LOW);
delay (39);
digitalWrite (2, HIGH);
delay (38);
digitalWrite (1, LOW);
delay (37);

    digitalWrite (1, LOW);
delay (60);
digitalWrite (12, LOW);
delay (59);
digitalWrite (2, LOW);
delay (58);
digitalWrite (11, LOW);
delay (57);
digitalWrite (3, LOW);
delay (56);
digitalWrite (10, LOW);
delay (55);
digitalWrite (4, LOW);
delay (54);
digitalWrite (9, LOW);
delay (53);
digitalWrite (5, LOW);
delay (52);
digitalWrite (8, LOW);
delay (51);
digitalWrite (6, LOW);
delay (50);
digitalWrite (7, LOW);
delay (49);
digitalWrite (12, HIGH);
delay (48);
digitalWrite (1, HIGH);
delay (47);
digitalWrite (11, HIGH);
delay (46);
digitalWrite (2, HIGH);
delay (45);
digitalWrite (10, HIGH);
delay (44);
digitalWrite (3, HIGH);
delay (43);
digitalWrite (9, HIGH);
delay (42);
digitalWrite (4, HIGH);
delay (41);
digitalWrite (8, HIGH);
delay (40);
digitalWrite (5, HIGH);
delay (39);
digitalWrite (7, HIGH);
delay (38);
digitalWrite (6, HIGH);

     digitalWrite (12, LOW);
delay (60);
digitalWrite (1, LOW);
delay (59);
digitalWrite (11, LOW);
delay (58);
digitalWrite (2, LOW);
delay (57);
digitalWrite (10, LOW);
delay (56);
digitalWrite (3, LOW);
delay (55);
digitalWrite (9, LOW);
delay (54);
digitalWrite (4, LOW);
delay (53);
digitalWrite (8, LOW);
delay (52);
digitalWrite (5, LOW);
delay (51);
digitalWrite (7, LOW);
delay (50);
digitalWrite (6, LOW);
delay (49);
digitalWrite (1, HIGH);
delay (48);
digitalWrite (12, HIGH);
delay (47);
digitalWrite (2, HIGH);
delay (46);
digitalWrite (11, HIGH);
delay (45);
digitalWrite (3, HIGH);
delay (44);
digitalWrite (10, HIGH);
delay (43);
digitalWrite (4, HIGH);
delay (42);
digitalWrite (9, HIGH);
delay (41);
digitalWrite (5, HIGH);
delay (40);
digitalWrite (8, HIGH);
delay (39);
digitalWrite (6, HIGH);
delay (38);
digitalWrite (7, HIGH);
}