You can take the grass shortcut on section 1, but the double shortcut on section 3 is a must. Keep in mind the shock tends to happen here, so use a dodge item at or before the shortcut.
Arriving from Mario Bros. Circuit, Whistlestop Summit, Desert Hills, Wario Stadium, or at the end of the Ice Rally
Also known as Crown City lap 2. Be careful not to overbag the route since you want to be in the front for the final lap since this version does not have many shortcuts on the track itself to make a good comeback.
Arriving from DK Spaceport, Koopa Troopa Beach, or Faraway Oasis
Also known as Beach Crown City. Bag the route as usual, and then for the final lap, there’s a big grass shortcut in the halfpipe. You can also take another off road shortcut just before the finish line.
Arriving from Peach Stadium, Moo Moo Meadows, or Choco Mountain
Also known as Ocean Crown City. Just before the water section, there is a glider to the right that you can get to by shrooming through some off road, and by using this glider you can avoid most of the water. Chaining a star into the second item set will also allow you to get to the glider while also being protected in a common shock spot.