Drawing machine

hi !
 we are creating a drawing machine that does mistakes and turns red (LED) after the mistake.
This is the code so far : 
/*
  Blink
  Turns on an LED on for one second, then off for one second, repeatedly.
 
  This example code is in the public domain.
 */
 
// Pin 13 has an LED connected on most Arduino boards.
// give it a name:
int led = 13;
#include <Servo.h>

Servo servoMain; // Define our Servo
Servo servo2;

// the setup routine runs once when you press reset:
void setup() {                
  // initialize the digital pin as an output.
  pinMode(led, OUTPUT);  
servo2.attach(9);
   servoMain.attach(10);   
}

// the loop routine runs over and over again forever:
void loop() {
   turnRight ();  // Turn Servo Left to 45 degrees
   delay(3000);
servo2.write(0);
delay(1000);
servo2.write(20);
delay(1000);
  digitalWrite(led, LOW);   // turn the LED on (HIGH is the voltage level)
  delay(2000);               // wait for a second
  digitalWrite(led, HIGH);    // turn the LED off by making the voltage LOW
  delay(1000);               // wait for a second

}

void turnRight() {
  servoMain.write(180);
}


But right now, the Servomain is doing a circle (this is what we want) and the Servo2 is moving sometimes : it is the mistake. However, we do not now how to make the light on after the mistake for a few seconds and then off again before the next mistake. Also, what would be awesome is if we could have the mistake randomly.
Thanks for your help !

check this out.

So you basically wants to get rid of the delays, wich make your whole code to wait.

See this: https://learn.adafruit.com/multi-tasking-the-arduino-part-1/using-millis-for-timing