To merge into traffic safely, it is essential **to ensure beforehand that it can be done without danger**. This involves following the **R.S.M. safety rule**, which consists of observing the road, making sure the maneuver does not pose a risk to other drivers, and properly signaling the intention to merge, either with the arm or with the turn signals.

When entering a road, it is crucial **to yield to other vehicles** without endangering them and not becoming an obstacle for them. This means that, if necessary, you should stop at the beginning of the acceleration lane until traffic allows, and then merge by adapting to the speed of the other vehicles.

Therefore, the priority is always to ensure that the merge is carried out safely, without putting other road users at risk.