Keys
This guide is particularly written for keyboard users, but the same principles apply no matter what interface you use to race. Here are the keys for certain actions here:

Drift Key - Shift
Item Key - Control
Accelerate - Up arrow -OR- W key

Turn Off Aids and Auto Settings
We're going to do this the professional way; as a result, you'll need to turn off all driving aids and assists in the settings to gain full control over your drifts and angles.

How Does Drifting Work?
Pressing or holding Shift will trigger a drift. Drifting allows you to make sharper turns and also charges your nitro boost gauge faster in Speed mode. Performing a drift correctly will also give you a slight instant boost.

Getting the Right Angle
Note that the longer you hold Shift, the touchier your turn will be. By tapping shift while turning right, you can hold down your right arrow key with no fear of turning too sharp and spinning out.

If you hold shift, holding down your right arrow key with it will trigger a very sharp turn which will likely throw you into the wall.
Holding shift longer is useful for getting sharp turns, but be sure to release it before you spin out.

Finishing the Drift
Release shift if you haven't already. Straighten your kart by counter steering, which is simply turning left after a right hand drift, or turning right after a left hand drift. If you drifted too sharp, hold shift again while counter steering to straighten your kart.

Getting the Boost
When finishing a drift, you can perform an instant boost that brings you back up to speed.

To achieve this boost, accelerate right as your drift finishes. Right after your counter turn to straighten up is finished, release the accelerating key and immediately press it down again. Timing it correctly will give you an instant boost. A good indicator that your drift has ended and that you can instant boost is when the tire marks stop appearing behind you.

Nitro Boost
Drifting is a crucial aspect of Speed mode, as it decreases the time until your next nitro boost tremendously. Using a nitro boost just before a drift will give a wider, longer, and faster drift that will fill up the nitro gauge much more than a drift without the boost.

This also allows you to maintain top speed on a drift. Doing so is just like a normal drift, but you generally only need to tap shift instead of holding it when using nitro on a drift to maintain better control.

Be sure not to let off of the accelerator while drifting as that will cancel the boost. Don't go for the instant boost at the end of your drift if your nitro boost is still active; doing so will cancel the nitro and you will lose speed. Only go for the drift instant boost if your nitro ends once you finish your drift.

Filling the Gauge
There are several factors that determine how much of the nitro gauge is filled when drifting. Here are a few:

1. Speed
2. Tension
3. Angle

Speed
To get the most out of your drift, use a nitro shortly before pressing shift for better speed. The faster you are drifting, the faster the gauge will fill up. Drifting downhill with nitro fills a large majority of the gauge if not all of it.

Tension
Tension is how much your kart is already turning before beginning your drift. If you start drifting while driving forward, you have no tension. If you start turning and immediately start drifting, you will have very little tension.

The more tension you have before starting your drift, the more your gauge will be filled. This is the key factor for getting perfect drifts and non-stop nitro.

Angle
The angle of your drift will also determine how much of the gauge is filled. It's hard to explain the correct angle in words, though. Wide drifts fill up the most, but not too wide. This is something that can really only be learned by experimenting and practicing.

Short Long Drifts
This technique is probably the hardest drift it master. The idea is to complete a very short drift to build tension and fill the nitro gauge a little, and then proceed to make a wide drift immediately after the short drift ends. Doing these correctly will fill the entire nitro gauge in one go.

First, start the short drift. Start turning the way you want to go, and tap shift. Immediately counter turn, and as soon as tire marks stop appearing behind your kart, turn back to the way you want to go and start a longer, wider drift. If you don't have enough room and the larger drift will throw you into the wall, counter turn and hold shift to straighten your kart.

It's hard to get down at first, but once you do it once you can't stop doing it. This technique is really useful but also keep in mind how much of the nitro gauge is already filled. If you are already half full and a normal drift will top it off, just go for the normal drift. Your nitro gauge does not stack, so any "leftovers" will not get put towards the next nitro. You only need to go through the trouble of a short-long drift if your gauge is almost empty. However, if you are playing duos or squads, doing these short-long drifts will increase the blue gauge significantly too.

And that's basically it! The best way to learn drifting is to try it out yourself as not every aspect of a drift can be explained easily.

Thanks for reading!

Updated 2/24/2023 (mm/dd/yyyy)
Added more details to filling the nitro gauge.