While you're unemployed, don't sit around staring at the t.v. or computer screen all day. Volunteer. Volunteering keeps you up to date on job skills and can even help you learn something new. It demonstrates that you are a go-getter, always ready to try something new.
Say you have worked as a vet tech for a few years, and you just go laid off. Find work volunteering at your local animal shelter. Perhaps the shelter is affiliated with a veterinary clinic. When you volunteer, you might just learn about a new piece of technology or procedure that you had never used in your previous job. When you find your next job, you are already set to use that new skill. You may even be hired just because you are one of the few people applying who have any experience with it. Volunteering often provides free job training in some respects. Take advantage of it.
Taking the Initiative
It is easy to fall into the "I have no job" blues. Sitting around all day in your pajamas, constantly checking your email for an interview invitation is not going to get you a job. Employers want to see that you constructively used your time off to help others and learn a new skill. If you are entering a new career field, in between jobs is the perfect time to volunteer to learn more about that field. When you apply for a job in that new industry, you demonstrate that you are serious about learning all you can about the new field. Working without pay carries a lot of weight with employers.
Finally, as a volunteer, you may be the first to learn about a job opening in the organization or within a partner organization. People within the organization already know how you work, and they can testify to your work ethic, passion, willingness to learn, and your skill set. This goes a long way with employers as they generally will prefer to hire someone they already know and trust. They also do not have to train you as much as they would another employee, saving them more time and money.
Volunteer at least a few hours a week while you look for another job. The benefits to your personal self-esteem and to your job search make the effort and time worth it.