bricked arduinos

I have two bricked arduinos. Well IDK if they are bricked. But I programmed them while they were still externally powered and it messes them up. Not sure what it does but I figured out I needed to use the pololu usb programmer to do it. I got it working a long time ago but I forget what to do now. Any help?

Have you tried using manual reset when programming? Hold down the Reset button, click on the upload button, release the Reset button when you see a blink of the receive LED.

didn't do anything. and no matter how much i search i can't figure out how to use the usb programmer to flash the arduino.