Optional Practical Training (OPT) allows F-1 international students to engage in temporary employment for practical training directly related to their majors. F-1 students may be eligible for a total of 12 months of OPT. To apply for employment authorization for Optional Practical Training, students must attend an information session presented by International Student and Scholar Affairs or have viewed the OPT Informational Video within the current academic year. Students are not required to have a job offer to apply.
If your program end date is May 18 or 19, 2019, then you should be thinking about your Post-Completion OPT application timeline. USCIS has very specific deadlines that must be considered when applying for OPT, and you should expect USCIS to take more than 90 days to process your OPT application.