To amplify Arduino PWM from 0-5 volts to 0-10 volts using an LM324, a higher voltage supply of about 12 to 15 volts is necessary, as op-amps cannot output more voltage than their supply. Users are advised to explore DC to DC step-up voltage converters to achieve this. It's important to avoid powering devices directly from the Arduino; instead, use the Arduino signal to control an external power source. The output voltage requirement and impedance will depend on the specific application for the 10V output. Proper power management is crucial to ensure reliable operation.