Being short, you'll need to get each track corner doing the less turn movement as possible, this is because the most you turn the most your car will drift, then if you drift you'll be losing speed.

For first, the objective in driving through a corner is to have the fastest possible speed at the exit or the last corner of a series. The last corner exit before a straight is the most important segment, since it'll define the fastest speed which you'll reach the next corner.
The yellow line indicates a path which maximizes the radius of the turn, or attempts to make the turn as straight as possible. It's important to not hit/crash the track limits/walls

There are also some different ways to take corners depending on how series are set - complex corner sets:


So:

• You should not drift.
  
• Turn as straight as possible.
  
• Get corners/90° sets from out to in, and then out again - see first picture.

It's important to pick the best car for the track you'll race. Each car can offer a different and situational "power".

For example, high turning cars will turn faster than others also if their grip is high, just like the Ellipse 212R will get faster those corners, but they can not deal very well with straight ways.
So, you should pick high steering cars for high turn demanding tracks or tracks with very difficult corners / square corners and no straight ways.

Btw, there's a special case you should consider - you can also go for a high power and nitro car for high turn demanding tracks if it's raining, since your car will turn and drift faster on the wet road, so you can pick a car without turn or grip, centering all the tune up in power and nitro.

Also, you should use the boost for straight lines, letting first nitro bar reach full.

Practice playing the free mode, driving through the city, memorizing the most difficult corners - use a D class car.

And the most important, have fun. :)

How to not to suck be better at daily challenges!

Introducing some quick pro tips to improve your times at dallies, separated by the class of vehicle you're supposed to drive:

Before starting with low tier cars which interestingly doesn't mean the easiest challenges to succeed on track, I'll teach you some tips in general, so you can get in shape before going to the juicy stuff!

GENERAL TIPS:
1) 1st lap. -Everytime do a recognition lap without any boosting, so you can see every corner and learn how to beat them, especially with long tracks. You can also drive more than 1 lap without boosting; I do recommend repeating until doing the lap with no wall hits/crashes!

2) Hotlaps. -Start searching for perfect boosting spots, preferable long straights, or fast corners. Before you start recording your time, remember to do the 1st lap with boost gauge at full, so you can boost before the start line, and gain some extra time (the nitrous gets refueled after passing the goal line).

3) Nitrous. -Don't ♥♥♥♥♥♥♥ leak your boost bar! Always be care of your nitrous, if you are close to get full of, just BOOST! When boosting you'll notice track sections that are better for boosting than others. Anyways, You'll prefer to stay calm, and don't waste it. You need it for sure in long straights.

LOW PERFORMANCE (E, D):
These daily challenges are the most tricky ones, because the racing line means a lot! Records between drivers are almost as close as 0.001 seconds very often.

1) Playing with gamepad or keyboard, no matter which one you use/prefer, driving low perf. cars will require you to do turn-taps, so your car don't slide/drift. Turn-tapping consists on... tapping constantly the turn button so the car angle changes slightly without drifting. You'll need to follow a correct racing line to perform this correctly, otherwise you'll end crashing or sliding all over the track.

2) Nitrous. -Boost gauge is really important on low tier cars, since they aren't so powerful at all. You'll need to save the full bar, and run it entirely in one shot every single time. Just remember to use it on straights or fast curbs, and do full boost before crossing the goal line to start recording your time.

3) Be aware of drifting. -Not only while turning, but boosting. Since the nitrous will run you faster, that may affect your grip while cornering.

4) Do not use the brakes. -For hard turns, you can slightly release the gas, and let it go, so you don't drift.

5) Snow conditions. -"This is a special case where you can drift as long as you want". Snowy tracks will let you go faster through corners without losing almost any speed. Be aware of the nitrous on this challenges, you should not boost + drift.

HIGH PERFORMANCE (C, B, A):
1) Keep your throttle trigger pressed EVERYTIME! Just brake slightly when you need it without releasing the gas.

2) As always, watch your boost gauge, so you don't leak.

3) Do not boost, and turn/drift at the same time, that will make a several waste on your nitrous, because the car doesn't accelerate when sliding.

4) You can use the handbrake to beat hard turns, and hairpins without losing any speed at all.

5) Practice a lot... :)

I'll be adding more content as I look for more pro tips, for now this is all I can attach - it was a bit rushed.

"See you in the track".