How to download and upload digistump Attiny85

void setup() {                

  // initialize the digital pin as an output.

  pinMode(0, OUTPUT); //LED on Model B

  pinMode(1, OUTPUT); //LED on Model A   

}

void loop() {

  digitalWrite(0, HIGH);   // turn the LED on (HIGH is the voltage level)

  digitalWrite(1, HIGH);

  delay(1000);               // wait for a second

  digitalWrite(0, LOW);    // turn the LED off by making the voltage LOW

  digitalWrite(1, LOW); 

  delay(1000);               // wait for a second

}