Impairment is a factor in many serious pedestrian collisions. In 2016, over a quarter (26.4%) of pedestrians involved in fatal collisions were legally impaired!
So even when you make a safer choice and choose not to drive after you've consumed alcohol or drugs, you do still need to be careful as a pedestrian. Remember, the reasons you shouldn't drive when impaired (impaired judgement, decision making, reaction time, coordination, etc.) still exist if you are a pedestrian. When impaired, you're more likely to cross the road in the wrong place, travel too closely to oncoming traffic, or to enter a crosswalk when it's not safe.
You can use many of the same precautions as a pedestrian as you would if you were a driver. Have a designated driver take you home. Or a "designated walker" who can help you stay safe as you walk. Make sure this person is decided on before your event. Also consider whether you need more than one DD to help get everyone home safely. Or consider taking a taxi or ride sharing service.
Also consider making yourself as visible as possible if you'll be walking home at night. Think about brightly coloured or reflective clothing or items to help drivers see you in the dark. Cross at brightly lit crosswalks and avoid jaywalking.