Retail Fraud / Shoplifting: First Time Shoplifting in NYC

My question involves criminal law for the state of: New York City
I was recently arrested for shoplifting about $150 in merchandise. First time, previous clean record, misdemeanor, I am 23 years old. I have my court date in a couple of days and would like to know what I should expect. I do not have a lawyer nor can I afford one, but should I ask for a public defender? And if so, when should I ask for one? Is it okay if I go in without a lawyer and plead "no contest"? If I do plead "no contest", what will happen? Second option: can I plead guilty to Disorderly Conduct or ACD or does the judge have to give those options to me first? What is the best thing I can do (without a lawyer) to avoid getting a permanent record?? What exactly is ACD? Is there any way that I can get out of this with no record??? Please help!