How can I increase my chances of getting into a university after I have submitted my application.
The only opportunity you have to increase your chances are if there is significantly new and impactful information to inform the Admissions Office of things that are not on your college applications.
Example of this might be: winning a State or National scholarship like being nominated for the US Presidential scholarship, winning a State or National title for either an athletic sport, music/dance/theater/speech/debate/science competition, getting a huge improvement on your standardized test scores, or some global event like winning a Silver Medal in the Olympics. If you don't have significant new information to add on your admissions file, it's best to let the process work itself out.
If you are wait-listed, there are definitely more things you can do like write a Letter of Continued Interest, get add'l recommendations, submit new test scores and honors.
Good luck.
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