This is an instruction about the new process of obtaining certificates from FNMT-RCM. This process is based on a new key generation software that allows obtaining certificates through any browser and operating system. It is only necessary to perform the process on the same device, with the same user, and not to format the device between the request and the download of the certificate. The process here described is to obtain a natural person certificate, being analogous for the rest of FNMT-RCM certificates, except for the differences in the download process.