The stock stereo in a Nissan Micra does the job, but it's not the fanciest thing available on the market. Today's car stereos have features like Bluetooth, iPod integration, and even in-dash CD changers. Because of the size of the factory Micra stereo, installing an aftermarket stereo is straightforward to accomplish. First though, you have to remove the stock stereo.
Unscrew the two screws located just above the stock stereo using the Phillips-head screwdriver. Then pull out the astray with your hands. Remove the two screws behind the ashtray using the Phillips-head screwdriver.
Place the hook tool in the seam between the dark grey bezel fitted around the stereo and the vinyl dashboard, then twist the handle so the hook on the tool is behind the panel. Pull the tool towards you to release the bezel from the dashboard. Once it's free, pull it off all the way and set it to the side.
Unscrew the stereo from the dashboard. Then pull it out and disconnect the wiring on the backside.