A-Class Driving School's Online Driving Tutorial -
Traffic lights and traffic light controlled junctions

Some sets of lights appear to be confusing on approach. The more experience you gain, the less daunting they become. Once you get to the partly trained stage you will be required to handle and deal with these in a slightly different fashion.

The moment you see them, check your mirrors to see how close the car behind is as you may have to reduce your speed. When approaching red lights, keep both hands on the wheel until you stop. Keep it simple. Taking hands off the wheel to adjust your gears unnecessarily leads to potentially putting the car into the incorrect gear.

Your hand may also apply the handbrake whilst the car is in motion resulting in an abrupt stop, damaging the car and being marked down. Keep the car under your control, stop, then apply the handbrake to secure it from rolling away and having someone shunt you forward from behind. Try to wait in neutral to rest the car and your feet.

You need to be able to display observational skills and general driving knowledge. Look to see what the other lanes of traffic are doing. You essentially need to be able to pre-empt the traffic lights. Look for tell-tale signs. The colour of the lights for the crossing traffic, are there any green men on the pedestrian crossing yellow boxes, are the lights making the crossing sounds. Try not to get the car ready until the last possible moment. The examiners do not want to see you constantly down on the clutch in first gear on the bite.

You must be able to show you understand how traffic lights work and that you are prepared to rest your legs and the car.
Observe. Some times the lights are red for what seems like an age. Look busy. You need to be taking in all of what is happening. Keep checking your mirrors. Cyclists could potentially come up from behind on either side.

The car needs to be prepared so when your lights turn green, you move away. You don't want to be setting gas and finding the bite as the lights turn green. You'll be slowing the flow of traffic behind you and the examiner will mark you down for not making progress. Remember, every colour except green means stop, only proceed when it turns green. Make sure you know the sequence, see diagram opposite.

Filter lights 

When turning right at a crossroads/T-junction, if there is a filter light, you may proceed forward into the junction when the main light turns green. Then you wait for either the cars which are coming towards you to stop or for the filter light to come on. If the main light is red, but green filters are on, you have to wait at the line.
Some times the filter lights don't work or is operated with cameras and pressure pads. If you are sitting waiting for a filter during your exam and it doesn't come on, you could be failed for not making progress.

The Highway Code says "153: Green filter arrow. This indicates a filter lane only. Do not enter that lane unless you want to go in the direction of the arrow. You may proceed in the direction of the green arrow when it, or the full green light shows. Give other traffic, especially cyclists, time and room to move into the correct lane."

The sequence of traffic lights

traffic light sequence

When the green arrow is on in the direction you wish to travel, it should be safe to make your turn.

filter lights

Make sure you get in the correct lane early when it is safe to do so.  A lane change would require a mirror and a signal.

filter lanes and lights