Around half way down the slip road, you will need to apply the MSPSL routine.
Check the interior and right mirror and signal to the right. Remember, observations should have started way back at the earliest point, so the position will depend on where you intend to join in relation to your speed. Speed is dependent on the traffic on the carriageway and as you join you will need to look in your interior mirror to ensure traffic isn’t too close behind you.
Joining a dual carriageway is the most difficult part for most learner drivers. Providing you match the speed of the traffic on the carriageway, mark your joining place at the earliest opportunity, stick confidently with your joining place by use of accelerating or slowing, then with plenty of practice it becomes easy.
If for instance you can see that the lorry is going slower than you, hit the gas and aim for the gap in front of it - but keep an eye not to go over the speed limit.
When joining a dual carriageway, it doesn't always mean that you need to slow down - sometimes by far the safest option is to hit the gas and get to the speed limit.