As someone facing a DUI, it's of the utmost importance that you do all you can to protect yourself. When you're pulled over, you know you're potentially facing trouble. You drank, but that in itself isn't enough to result in a DUI unless you were driving dangerously.
If you are arrested, you'll be taken to the police station. Upon arrival, you'll likely be searched, and any money or property will be taken, documented and inventoried. You should get these items returned to you upon release.
During the intake process, you'll be asked questions about your physical health, medicines you need and your mental health. Keep in mind that you should stick to facts and not stray into a conversation about possible charges. You'll be told the driver's license's suspension procedure, and you'll also be part of a short observational period. After that time, an Evidentiary Breathalyzer Exam is given. You will receive a 12-month suspension of your license if you decide not to take the exam.
Following this, you can be interviewed and read your Miranda rights. Typically, anything you say or do cannot be used against you if the Miranda rights aren't read before your interview takes place.
It's a good idea to reach out to an attorney and assert your right to an attorney at this point to make sure you are treated fairly and without bias. It is generally not in your best interests to participate in the interview without your attorney present, because you may say or do something that could incriminate you or make your case more difficult.