The only reason to take Step 2 prior to applying for the match is if you feel your step 1 score is not high enough. Most people who do well on Step I do not take step 2 before the match, as you run the risk of scoring lower.
Start thinking about where you'll do your aways now. Certain places (Columbia, Barrow) get 15-20 rotators/year, and spaces can fill fast. Conversely, if you are looking for a letter from you aways, you might be better served going to a less popular program (ie Pittsburgh, Michigan, UVA) where you are likely to leave a more lasting impression.
Probably the best place to start research is at your own school. If you just want a quick-hit pub, try doing some chart reviews/case reports with attendings that you know publish a lot. If you have some elective time, a month doing lab work can help too. Don't underestimate the importance of research...I know of several people this year with board scores in the 250's who were snubbed from the top programs because they didn't have any.
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