Pre-5K Race Routine
Get to the race early. I would suggest 45 minutes to an hour before the race starts. This will allow you to get a good parking spot, along with giving you plenty of time to use the bathroom, warm up, stretch, and mentally prepare for your first race. Lines to the port-o-potties will be long and they may run out of toilet paper, so I suggest bringing some with you in your bag that you pack the night before the race.
As the race start approaches, you need to do a light warm-up that includes some dynamic stretching and a walk or light jog for 5 to 10 minutes. Do not stretch cold muscles. Dynamic stretching is better than static stretching before a race because you will warm your muscles up through the dynamic stretching without risk of injury.