If you choose to perform maintenance tasks for your KTM 505 SX F then it will always be a good plan to have access to a Workshop Manual to use as a reference should you need to know tips to remove a certain component like the Door and fit it again perfectly.
KTM 505 SX F Workshop Manuals will give specified diagnostic guidelines with regards to your car therefore if something is faulty it will help you understand what the issue is and tips on how to resolve it. After that you can evaluate if this can be done yourself or in the event the job is simply too big you can still make a reservation for your 505 SX F right into a nearby friendly mechanic.
KTM 505 SX F manual