You must first identify a position to apply for.
Agencies announce their SES vacancies on OPM's website
USAJOBS. From there, you may
download information on vacancies of interest to you, complete the
application procedures, and submit your application to the agency that
has the vacancy. The agency submits the executive core qualifications
of the person selected to a Qualifications Review Board (QRB) convened
by OPM. The QRB must certify all selectees before they can be appointed
to the SES. Further information about the
selection process is
available elsewhere on this site.