Most federal jobs announcements list skills the applicant must possess in order to qualify. Your application package must therefore demonstrate that you have those skills. Don't assume that because your federal resume describes some great accomplishment, the human resources reviewer will know what skills it took to get the job done. Your skills have to be explicitly stated.
Here is some advice that I am addressing to graduate students, but really applies to anyone. During your time as a graduate student (or in college, high school, technical school, on the job, where ever), keep a skills notebook. As you learn new techniques or use new instruments record the specific procedures, pitfalls, and tricks you've picked up. Collect protocols that your lab uses. It this way you have a reference manual for future use at another institution. Don't limit yourself to your own lab. By exploring the techniques of others in different fields where different questions are asked you'll gain new perspectives on your own work. You'll also be increasing your versatility and become well prepared for writing your federal resume. This goes for statistics and time in the field as well.
For those of you further along, you already have amassed a huge range of skills even if you don't know it. You've probably never had to list them all out, but it's an important exercise because skills are central to the federal resume and electronic resume, as well as being important for business resume. CV's these don't usually have lists of skills, because the people who'll be reading your CV are trained in the same techniques that you are and know what it takes to accomplish them.
One way to create a comprehensive list of skills is to go step-by-step in your mind through various projects you have done. Start with the brainstorming and conception of the project and move through preparation, collection of samples, exploration and analysis of data, finishing up with writing and presentation. Everything counts.
For example, suppose you are studying water quality in a lake. You'll have to figure out what type of samples to take and when, actually take the samples, process them, examine the data, and summarize everything. Some of the skills needed to carry this out include field survey design, operation of boats, collection and proper handling of water samples, various chemical analyses, data management and exploration, various statistical analyses, and report writing. For your federal resume you'd list the specific chemical and statistical analyses. Also include examples of instruments or programs used.
On your federal resume skills can be simply listed under headings of your choosing. Categories could be field skills, laboratory skills, or computer skills. You might want to break up categories more specifically, like data management and statistical analysis. The categories you choose should reflect your field, but you have the freedom to customize your federal resume to best reflect who you are, what you've done, and how it relates to the job ad you are answering.
Here's an example:
Lists of skills on the federal resume are most important for applicants at the beginning of their careers. As seniority is gained, accomplishments will become more important than skills. Thus as you progress, skill lists should become less prominent and eventually dropped altogether. At the same time, specific duties within job descriptions increase, including lists of major accomplishments.
It's important to note that the purpose of grad school, or any training program really, is not simply to amass skills. Without the knowledge and experience to use them, skills are useless. Skills do, however, have critical roles to play. If you take the time to sit down and list all the skills you have, your federal resume and application package will benefit. Seek ye out skills!