I would get up at the crack of dawn and ride before the trails are overrun by sleds that will create 2 foot high moguls by 2 PM (not the groomers fault). Also, when you leave Cherrywood, ride across the street and take a left and ride the ditch to the trail by the railroad tracks (422 south) and then left on 8 (east) to get out of the area towards Grand Marais. This saves you from riding the bumpiest part of the trail.
On your way back to Cherrywood go the same route backwards, then go past Cherrywood for a half mile to get gas and snacks.
Bear