If Immigration and Customs Enforcement (“ICE”) comes knocking at your door:

DO NOT OPEN THE DOOR. ASK TO SEE A WARRANT. ICE may not enter your home without a warrant signed by a judge. You do not need to open the door. You do not need to answer questions. Ask for the warrant to be slipped under the door. If they have a warrant that allows them to search your property, you must let them in, but you do not have to speak.
DO NOT ANSWER ANY QUESTIONS, EVEN YOUR NAME. You have a right not to answer questions from ICE. Tell them that you want to speak with a lawyer, even if you do not have one. Many organizations visit with immigrants in detention and can arrange for pro bono (free) counsel. That lawyer will be happy that you said nothing.
DO NOT SIGN ANYTHING especially an Order of Voluntary Departure, without first talking to a lawyer.
If you are arrested, REMAIN SILENT. You do not have to answer any questions or talk with the immigration authorities or police. Ask to speak with your lawyer or a lawyer who represents you. It is important that you:

do not answer any questions;
do not say anything about where you were born or how you entered the country;
do not show any documents (especially any false documents), except a letter from a lawyer;
do not sign anything, especially an Order of Voluntary Departure, without first talking to a lawyer;
do tell the Immigration Service official that you want your hearing in the city closest to where you live where there is an immigration court; and
do ask to talk to your lawyer.

New York

Chapter: Immigration and Undocumented Youth