This page should also separate time trials tactics from online tactics.
Tactics used to compete at Mario Kart DS.
The powerslide: To powerslide, hold down the R button whilst turning either left or right to perform a powerslide. This is useful for turning corners more quickly than simply pressing left or right. This is sometimes also called drifting.
Hopping: To hop, repeatedly press R. This is useful to re-align the kart in the direction you would like if you have been spun off course or facing the wrong direction. It is also useful for keeping a reasonable amount of speed in surfaces you would otherwise lose considerable speed on such as mud or grass.
Mini-turbo (MT): To perform an MT, whilst powersliding tilt the D-Pad from left to right or vice-versa until you see the sparks at the back of the kart change from blue to red. Once red, release the R button to perform a mini-turbo (MT). This is useful in gaining a short burst of speed and can also be utilised on straights if performed quickly and in succession. This tactic is most commonly called 'snaking' as it resembles a snake weaving from side to side.
Utilising items: There are various items in Mario Kart DS Grand Prix, VS., and Wi-fi matches, and there are numerous tactical ways of using a handful of these items.
Blue Shell: Although this may be considered a cheap tactic to win, a good way of using this item is holding onto it until near the end of the race at which point you release it. If you are close enough to 1st place this could win you the match as they would be unlikely to recover in time to regain the position, meaning you win.
Red Shell: There are various excellent opportunities to use this item to guarantee you to move up a position. An example is to release it just before the well jump in Yoshi Circuit (GCN). This would then cause them to fall down into the well and cost the racer valuable time whilst you overtake them.
Mushrooms: Mushrooms can be used in places where you would normally lose speed, thereby catching up to any racers in front of you. A good example is through the water on Cheep Cheep Beach after the 2nd zipper jump to the right. Another example is hopping over the clouds on Sky Garden (GBA) which, if used in the right places, can cut off a large section of track.