What is the best way to obtain funding for living expenses while going to UNLV?

A part-time job.

You can either look for an on-campus job (usually the campus Financial Aid office oversees the postings for on-campus jobs.) Generally the food service jobs and jobs for library student assistants are the most plentiful as they are the divisions on campus that are open the most hours of service. I recommend looking for a job at the campus library, myself. Work schedules for on-campus jobs are often easier to manage with class schedules than those for off-campus jobs.

You can probably earn more per hour at an off-campus job, but transportation to-from the job may be a bit of a hassle.

For students who are not US citizens, I think an on-campus job is the only option for legal employment.

Best wishes