Residency preparation begins during 3rd year while you are on your rotations. You should do your best to stand out by being proactive, asking questions, reading as much as possible, and perfecting your skills in performing the history and physical exam, as well as writing the SOAP note and H&P. On every rotation, try to sense whether you will be able to get a good letter of recommendation from your preceptor - these become invaluable toward the end of your third year when you begin putting together your residency applications. By doing your best to stand out as an exceptional student, you are getting a head start on your residency apps that will go out in a few months.
Careful planning is required to ensure your ability to return to Canada to practice. Your two options
are to complete an ACGME residency in the US with the aim of returning to Canada after you train,
or to try to match at a Canadian residency program. Both pathways are challenging, so follow these
steps to make it as easy as possible:
Figure out what you want to do EARLY. This means getting exposure to your fields of interest as early as possible to narrow the field. You won't be able to do the necessary research until you decide on a specialty, so be sure to get this done before the second semester of your third year. Your ability to match certain specialties will depend on competitive board scores, so keep this in mind while preparing for Step 1.
Once you know what you want to do, research! For Canadian programs, use the CaRMS website to analyze the competitiveness of your chosen specialty in recent years. Remember that DOs will be considered IMGs in CaRMS beginning in 2016 - IMGs have a designated number of spots per field in most provinces, so look at the IMG data for the number of applicants per spot available. Decide whether you are up to the challenge of matching CaRMS, and if you are, prepare to apply for Canadian rotations and to take the MCCQE Part I and NAC OSCE. For ACGME programs in the US, you will need a visa! Look up all the programs in the country for your chosen specialty, and find out which ones will sponsor you for a J1 or H1B. Plan your 4th-year electives around the programs where you have a shot.
Apply broadly! There are thousands of applicants in the US and Canada for a very limited number of residency spots. You NEED to apply broadly to maximize your odds of matching. Now is not the time to penny-pinch; the costs of applying and interviewing are a drop in the bucket at this point.
See below for more information on residency in Canada and in the US.