Depending on the situation, you may want to seek legal counsel immediately. In some cases, if you do not respond properly and within a certain amount of time, you may automatically lose your case. It is often not in your best interest to represent yourself in court.
Before meeting with your lawyer, gather as much information as possible pertaining to the case. Bring the paperwork that was delivered to you, copies of any legal agreements pertaining to the case (lease agreements, sales receipts, divorce agreement), records of communications (phone calls, emails, texts or letters), and information about the party suing you. Do not talk to anyone but your lawyer about the case.