It depends why you need to go there. Some have appointment but if you're going there to apply for government help, you can show up. The lines in the morning are very long. My experience is that the lines are gone by 3 PM. I have been there 4 times and I always went after 3 pm.
You can just show up. Best to come early (line starts forming at 7:00AM) for entry at 8:00PM. After going to see one of the clerks at the window. They Will ask you what you are applying for. You will be given a number and directed based on the assistance you are applying for.
I would go b4 8am. Mon-Fri. If you missed an appt you need to call and reschedule because they may do that when get to the ofc if it's too crowded
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