Save petrol until maximum torque?

Hello guys, I always try to drive fuel-saving and always drive just under full throttle with accelerations to get into a high gear quickly. Now I wanted to know if it is more fuel-saving up to the maximum torque (are with me 3500 at full throttle) and then to skip a few gears (with the method I can switch from 2nd or 3rd to 5th), or if I pull up better up to approx. 2000 (still close to full throttle) and switch all gears through. I actually drive n ur in the city, car is a Suzuki Ignis 1.3 year 2000 with front drive (petrols).