Hi! First, I don’t know how the app review process differs entering from high school as an undergrad versus transferring from community college, but I imagine they’re looking for the same qualities. GPA is a factor but, as with a lot of/most private schools, the review process is holistic (case in point my grades were terrible). Excluding donating money for a new building I don’t think there’s anything specific you can do to better your chances in any concrete way, except presenting yourself as the kind of student they think would benefit from the environment and would also benefit the environment.
I mean I don’t think that JHU has wildly different standards or expectations for its applicants than any of its peer institutions, although I get the feeling that they’re a little bit more forgiving regarding grades if you seem like the kind of student who has proven their interest in a certain area, or if you really strongly voice your interest in a certain area. (I mean, I put this blog on my application - I’m not sure if the application people even looked at it, but I hope they did.) So if you have any concrete experience or proven interest in the area you want to go into I would definitely play that up. Otherwise my only advice is to be as genuine as possible in the written portions, like try to come off as a real person, but that’s just general advice.
Good luck!