Fishtails.. unlikely lah.. 
But agree with some professional coach can learn faster.
For starters, practice your footwork 1st (stationary), then try it
at lower speed on straight roads. Try brake and downshifting at the
same time.. if you do not blip your throttle and throw your clutch
while downshifting, the action will be rough and may unsettle the
car. Try blip the throttle before throwing your clutch to achieve a
smooth downshift.
Action goes this way..
1. Brake (into a turn)
2. Clutch in
3. Downshift
4. Blip throttle while still holding to brake (this is where
footwork comes in)
5. release clutch
Try performing step 2~5 within 1sec and at the same time achieve
smooth downshift (not by releasing your clutch slowly coz in a
race, your clutch will overheat in no time).
How much to blip? say you are in your 3rd gear and traveling at
150km/h, 5000rpm. you brake and slow to 100km/h @ 3000rpm, at this
speed, if you down shift into 2nd gear, your RPM should, say be at
6000rpm. This means you need to blip your throttle to 6000rpm
before releasing your clutch.
Hope its not too complex.. keke.. If still dun understand, try
signing up for an adv driving course (hopefully they still teach
this, coz nowadays all semi auto, computer blip throttle for
driver).
OK, having said the above, please drive carefully and responsibly
on public roads.
Cheers! 
