Today's workout starts off with a three-rep max in the back squat. You did this last week on leg day as well, and you're probably still feeling it—or at the very least, having flashbacks. You did it once, though, and you can do it again! This time, aim to increase your max weight. Your body has been getting stronger every week, and if you push yourself, your numbers will reflect that.
You're doing fewer reps on leg day than during some of the other body-part workouts, but that doesn't mean less weight. These reps should be heavy, pushing some of the largest muscles in your body to grow.