First, you want to look at a couple of organizations and see what kinds of positions are available. They may need anything from a marketing manager, an event coordinator, to somebody to be in charge of the finances. Look at all the jobs that are available so you can get an idea of what's out there.
In many cases, you will probably have to call the organizations and ask what kinds of positions are available as you won't find information on this on their website. Don't stop at one organization and try to contact as many as possible to get a broader look at the jobs and see what you might be interested in.
Second, take a good look at yourself and think about all the skills you have. Do you have the skill sets to work in the nonprofit sector? You should also take a look at what kind of academic achievements you have as important jobs may require that you have a college degree in a specific area. For example, if the organization needs someone for their advertising, you will need to work with agencies and marketing departments.
Third, think about what issue is important to you. Most people are interested in a nonprofit profession because they care about certain issues. In some cases, you will be more difficult to find a specific position with the issue you want to support. You will want to weigh whether the job or the issue is important to you.
Many people care more about their passions rather than supporting their issues and would rather get a position in an organization with a cause they are not particularly important to them. Others may sacrifice the ideal position in order to work for an organization that supports a cause they sympathize with. There will also be financial matters you need to weight when it comes to these decisions.
Finally, look at the nonprofit profession and see if it works with your future. You will have to figure out whether or not this is something you can see yourself doing many years from now. You also have to consider whether the salary you get paid in these positions is something that will keep you satisfied over the long term.
So that's a quick overview of choosing a nonprofit profession. There are many things to consider when choosing a job in this sector. You have to really take some time out in order to do your research and weigh different factors before finally coming up with your ultimate decision.