What is the correct technique for changing gears smoothly without causing vehicle jerking?

1. Move the lever quickly with the clutch only part way down, to keep the change short
2. Release the accelerator, clutch fully down, select the gear, then let the clutch up progressively with gentle throttle
3. Keep the accelerator held while changing, so engine speed is already matched to the new gear
4. Glance down at the lever to confirm the gate before moving it, then return your eyes to the road