Carb loading has had a variety of approaches over the years.
Currently, one of the best approaches is loading up a few days before the race. Also, if you’re traveling to the race, doing a little meal planning before you leave will help. Either bringing all your own meals or knowing what local food options you have such as restaurants, grocery stores, or farmers markets will help in planning each meal.
Sticking with good, clean carbs such as oatmeal, fruit and quinoa will have a positive difference in your race.
Runners World has this article which includes some menu options for each meal…check it out and have a Great Race!