“Well before you turn right you should use your mirrors to make sure you know the position and movement of traffic behind you give a right-turn signal take up a position just left of the middle of the road or in the space marked for traffic turning right leave room for other vehicles to pass on the left, if possible”
“Wait until there is a safe gap between you and any oncoming vehicle. Watch out for cyclists, motorcyclists, pedestrians and other road users. Check your mirrors and blind spot again to make sure you are not being overtaken, then make the turn.” use your mirrors to make sure you know the position and movement of traffic behind you give a right-turn signal take up a position just left of the middle of the road or in the space marked for traffic turning right leave room for other vehicles to pass on the left, if possible”
"It is perfectly possible, and indeed unfortunately in this case, that there was a motorcycle somewhere in this triangle, I think, of invisibility. What he should have done and what would have amounted to discharging his duty to take reasonable care required him to do was to move over his car closer to, and perhaps even over, the centreline of the road before he made his turn so that in his wing mirror (let us call it, we all know it is no longer on the wing of a car but next to the door), could see right down past the side of the four by four and see whether there was anything there. The situation is that as The Highway Code says that before you finally move to take your right hand turn, you should check your mirrors and blind spot again."