New SIM800 library aimed at HTTP communication & GSM location

Hi guys! How are you connecting the reset pin to the Arduino? I'm using the same module, and I'm afraid to connect the reset of the module to a digital pin of the arduino to control it by software, because of the differences of the voltage. Should I put resistors in between this connection to lower the voltage?

Also is it normal, when I send the command AT+CPOWD to power off, it turns on after some seconds?
Is there a way to turn on the module with AT commands?