Get good legal advice
Get screened by a lawyer as soon as possible to see if you or your loved one is eligible for any legal defenses against deportation (“relief”). If you live or work in New York City, call 1-800-354-0365 between 9 am and 6 pm, Monday - Friday or call 311 and say "ActionNYC" to get a free immigration legal consult.
Be careful of scams!
Always keep your original documents.
If hiring a lawyer to represent you, always have a signed contract and make sure to review the document in your preferred language. Make sure both you and your lawyer sign the contract and you get a copy.
If hiring a private lawyer, always get a second opinion before paying and get a receipt for payment (ideally paying by check or money order instead of cash).