Application for admission to graduate school needs to be completed online. It requires GRE score, 3 letters of recommendation (minimum), TOEFL score, SOP (statement of purpose). The deadline for submitting the online application is around December 1 for mechanical engineering department. Once the application is submitted, it is reviewed by the admission committee. If successful in getting admission into graduate school, one can talk to professors in their field of interest to join their group as a research assistant.