1st Gear is used for moving off, manoeuvring and for creeping slowly in traffic and at junctions. 2nd Gear is used for moving off down very steep hills, building up speed after moving away and driving at low speeds. 3rd Gear is used to build up speed and when you need more power for climbing hills. 4th Gear is used for driving at speeds generally higher than 30 mph, where there are no hazards to confront. 5th or 6th Gear not all vehicles have a 5th or 6th gear, which gives better fuel economy.
To Practise - change UP through the gears on the road, first find a fairly straight, wide road where there is little or no other traffic. Move off in first gear and change into 2nd gear as soon as you can. Accelerate to about 15-20 mph, then change into 3rd gear. Accelerate in 3rd to 25-30 mph and then change into 4th. To Practise - change DOWN through the gears When you have built up your speed to 30 mph and you are in 4th gear, Check the mirror to make sure it is safe. Brake gently to slow the car down to about 20 mph. Release the brake and change into 3rd gear.
We can change down the gears in blocks, such as 5th to 2nd or 4th to 2nd. If you are driving along at 50 mph in 5th gear, and you want to turn left into a side road, you may be able to do so without having to stop, as you approach the junction you need to reduce your speed until you are going slowly enough to take the junction safely, when you have slowed down to a safe speed using the brakes, you have to select a gear that will drive the car comfortably at that speed, in most cars the best gear for the job will be 2nd, so move the gear lever directly to the second gear position skipping the other gears.