If you wish to undertake auto repairs on your Aprilia MX 50 Supermoto then it is usually recommended to possess a Workshop Manual to use as a reference just in case you need to know proven methods to take off a particular component such as the Gearbox and fit it again appropriately.
Aprilia MX 50 Supermoto Workshop Manuals will provide you with specific diagnostic guides on your car so if something is faulty it will help you work out what the issue is and tips to repair it. You can then evaluate if this can be done yourself or if the job is simply too big you can actually book your MX 50 Supermoto into a trusted car garage.
Aprilia MX 50 Supermoto manual