Do Not Drink Excessively and Drive
This may seem like a simple and obvious piece of advice, but it is amazing how many people think they can drive home when they are clearly intoxicated. Barring egregious police misconduct, not even the best lawyer can get you out of this bind.
Cooperate with Police
Do not act evasively. Police will generally treat you with more respect and dignity if you are nice to them. Have your driver's license ready when the officer approaches and always take a few deep breaths to relax so that you are not nervous when he greets you. Answer with one word answers when possible to avoid the illusion of slurred speech.
Quiet the Party Down
When the police knock on your door, you must quiet everyone down so that the police cannot determine how many people are there. If they feel it is a large gathering, and they suspect you of operating a tavern without a license, they may care more than if you have a few friends over.
"Silence is safer than speech." —Epictetus (c. 50–120 A.D.)
A driver's license is a privilege, not a right.
By accepting a license, you impliedly consent to giving a blood, breath, urine sample for testing of alcohol content if arrested for OWI. Failure to comply without legitimate (mainly medical) reasons will result in a 1 year driver's license suspension and will count as a prior OWI even if you are acquitted or the charges reduced/dismissed.