While it might seem like choosing a journal is something to worry about once your manuscript is written, it will actually save you time and trouble to think about this early on. Not all journals will accept certain types of publications, such as systematic reviews, and some will have requirements that you would need to meet in advance, such as registering a protocol.
While we'd all like our first choice journal to accept our manuscript, chances are we will need to submit to several journals before acceptance for publication. With that in mind, it is a good idea to choose a few appropriate journals in advance. This will help you to be aware of author guidelines and gear your manuscript accordingly.
JANE (Journal/Author Name Estimator) is a freely available tool that will help match your article with suggested journals. Simply enter the title and/or abstract of the paper in the box, and click on 'Find journals'. The more information you provide, the better your results.
If you use the citation software Endnote, it has a handy Manuscript Matcher tool. You will need to add your title, abstract and ideally link to the references you used for your paper, and it will suggest journals that would be a good fit.
Journal Citation Reports through the Web of Science Group provide a ranking of journals found in Web of Science by Journal Impact Factor. While not all journals are found in Web of Science, looking at a list of journals ranked in your subject category, can sometimes help to prioritize journals to submit to. Keep in mind, however, that a Journal Impact Factor should be used with informed peer review and not be the sole consideration in judging a publication's worth. One bonus of looking at these journals, however, is that the Web of Science group monitors and excludes journals that demonstrate predatory behaviour.
Journal Citation Reports are accessible to those with University of Toronto UTORID and password.
When choosing a journal, in addition to finding the right fit, you might want to consider publishing in an open access journal, which would allow for free and unrestricted online access to your work. This is also a requirement if you are working with a grant from certain funding institutions. The best place to find a reputable, peer-reviewed open access journal is through the Directory of Open Access Journals (DOAJ).