Please note that I am not a pro; in fact I would call myself lower than an amateur. So all the stuff below could be incorrect. Other guys on here will be able to give you better advice. But here are my thoughts:
Are you trying this in a DCT? If so, I'm pretty sure it does it for you.
1) It's harder to achieve precisely at low speeds and RPMs
2) First make sure you have the whole movement down right. Do it in neutral and try to achieve some different RPM values. Take note that the flywheel is not as light as the race cars that you see in videos, so it might not take a quick stab at the throttle, but a firm depress.
3) I find that I'm less jerky if I pay more attention to the toe part (i.e. the brake).