How To Apply for A Government Job 
As with most jobs, the federal government requires a resume. However, it is much different from what's expected in the private sector.  First, it can be anywhere from three to five pages in length.  A federal resume must nclude special keywords and phrases found throughout the vacancy announcement to pass the initial screening process.  Although there are similarities, each agency (and often each job announcement) will have specific information required in its own format, as specified in the vacancy announcement.  The information below will describe each category on a federal vacancy announcement. You'll need to understand what each category means to be successful in your search.
Many federal jobs open to the public, which means anyone may apply for the job. However, most announcements require American citizenship for basic eligibility.  If a vacancy is for Status Candidates only, it's most likely open to federal government employees only and those who have separated within the past three years or who are eligible for ' Preference points. Some positions are restricted to current agency employees only. Read the vacancy announcement carefully to determine eligibility.
Federal jobs usually list a  summary and qualifications for the position that must be demonstrated in your work experience.  You will be scored according to how your experience match the requirements.  The key to successfully submitting an application packet is to highlight the skills in the announcement as it relates to your work history, where appropriate, avoid unnecessary details that might be interesting but do not add value and can distract from more important experience.
Grade Levels
The federal government uses grade-and pay-level structures such as Schedule (GS) and Wage grade (WG) system to identify positions, pay, and seniority.  Most announcements require at least one year of experience at the next lowest level, although education can sometimes substitute for this requirement.
Specific instructions on preview questions will be listed in the announcement, but these can be confusing, especially in some of the systems. Read this information carefully, as some requirements can be very specific. Some statements are entered into an online field, while others must be uploaded as a separate document. Any deviation in required format can result in a rejection of the entire process.