I am considering applying for on Accounting Technician position (GS 5 - 7) with the Dept. of Defense that lists 4 KSA's. Are the KSA's listed in the order of their importance to the job? Two of the KSA's talk about "Knowledge of Joint Travel Regulations (JTR)" and "Knowledge of applicable polices (e.g. DoD, OMB, GAO) practices and regulations. Since I have never worked for the government how can I find the regulations so I can study them? I also have not been employed for the last 2 years, taking time off to help with family matters. Should I address this time off in my cover letter so there is no question about an employment gap? Otherwise, I have been steadily employed for 30 years.
You could account for the last two years in some fashion by calling your job title Self-Employed or Unemployed By Choice. Then you could state that you resigned from your previous position in order to settle a family estate and act as executor of a will (or some lingo like that). If you were involved in selling rental properties, etc., you could give a little insight into what you did. But you don't need to say too much about that particular work experience. Just account for it.
You are on the right track in terms of wanting to do some research into Joint Travel Regulations. Plug JTR into a search window and see what happens. A reference librarian could also help you locate the manual(s). Then you could talk in the KSA about how you are familiar with JTR. Also look over the job description in the position vacancy announcement, and try to use some of that lingo if possible. If you have ever done a job in which you had to research information and take actions at all times which were consistent with standard operating procedures and policies as contained in a specific manual, then describe that experience on that KSA since you were doing an equivalent activity. You need to convey a certain style in that type of KSA, and that style is that of an individual who is experienced in performing research into the rules and regulations governing activities such as travel.
"Knowledgeable of applicable policies" is a broad KSA. Isn't that a KSA that will favor people who have worked for those agencies before?
Sometimes KSAs are in order of importance, but not always. For example, if there is a "screen out" KSA, it is first on the list, and screen out means that it you don't possess that particular knowledge, skill, or ability, your other KSAs are meaningless. Be sure and apply for lots of other Accounting Technician positions, too. Those two KSAs seem very technical. Cynics sometimes feel that KSAs seem to be written with someone particular in mind. You might do best if you go for jobs which require more generic KSAs. Those very specific KSAs almost seem like they are designed to trap people who have never worked for those agencies. But again, if you can show that you have worked in environments in which you have had to be knowledgeable of the rules and regulations of other organizations (perhaps customer organizations), then you can show yourself as a generic fit for that position.