Whats the best way to commute from downtown to oak park after hours?

Hey guys

I am planning on moving to the city for a couple months for a work opopportunity ive gotten.

I work in the restaurant industry and for that reason , my hours will not be around the rush hours. And more times than not i will finish work around midnight.

Because its only a couple months i plan on staying with friends who live in oak park.

Was wondering how safe is the commute at those hours. I read that the fastest way is through the green line

Thanks in advance