Navigating the job market
The resume is one's "roadmap" of their career thus far. It is a brief encapsulation of jobs, skills, education, and personal information. That said there are no universal rules when it comes to resume content and style. Granted, there are guidelines and suggestions. There are "general" practices and "standard" formats. However, one can write a resume in whatever way seems appropriate for the job or the skill set.
Always editing
People should keep this in mind when writing their resume and they should also remember that a resume is a "living" document. This means that it is always changing, and in many ways people should be looking for ways to change their resume. In other words, they should look for additional education, experience, and affiliations so that they can expand their marketability.
Going in different directions
As mentioned, a resume does not have to be a fixed entity. If one is pursuing two different jobs, it is appropriate, if not encouraged, to have different resumes. Sometimes this can be difficult when a person has limited experience, but it is still important to put one's "best foot forward" when writing a resume.
Tailored to the job
Overall, the resume writer should highlight those skills and experiences that best fit the desired job. For example, if they are pursuing a job that fits with their schooling, they might list their education or degree first. However, if they are pursuing a job that is similar to a prior job that they performed, they might list that prior job first on their resume.
Keep it straight
The important thing to remember when working with multiple copies of resumes is that they have to be kept straight. Sometimes people edit a resume but don't take the time to re-read it before they send it out. This can be an embarrassing situation if a resume was "geared" toward a completely different job. It is also important that the resume be in sync with the cover letter, if that is sent out as well. Sometimes the cover letter can actually be the document that is most customized, because the person can write in narrative about their interest and relevance to the job.
A quick look
Overall, people should remember that a resume should be concise, professional, and easy to read. Regardless of effort, employers are not going to take a great deal of time reading a resume. It is a "gate keeping" device, but a crucial one. Edit that resume, and then edit it again, just for good measure. Finally, it is always a good idea to show one's resume to number of other people who will give honest feedback. That way, the sender will have some idea of how they are perceived.