Hardest part about driving?

A little trick that positions you in the lane you wish to enter in the turn is the same for anything from a sports car to an 18 wheeler. The only difference is how far you turn the steering wheel and how fast. (That has to be learned for your vehicle through practice.)

If doing a right turn: When you can look straight out the right side of your vehicle until you are looking straight down the part of the lane you want to finish your turn in, do the turn.

Hand over hand is a serious no no in any professional training. You shuffle the wheel between the hands so that if something happens you don't have your arms crossed and unable to correct quickly.

Turning left is done exactly the same by starting the turn when you can see straight down the lane where you want to end up driving straight to your left.

Many try to "arc" into the proper position and it can be done, but that requires lots of practice and knowing the corners of your vehicle perfectly. To learn that is easiest if you find an intersection that has the turning arcs marked on the ground and following the lines from start to finish of the turn while paying attention to how you have to turn the steering wheel to complete the movement. (Those are rare intersections, but worth finding if you really want to learn to drive properly.) Most new drivers "cut" the corner by turning too soon. That is a dangerous turn as it can cut in front of other traffic attempting their turns. watch a bus, or 18 wheeler making a turn and notice how the rear cuts tighter than the front. That is called off tracking and even a car does it a little. Ever seen a car turn too tight and "clip a curb"? The front tires made the turn, but the rear tires cut inside and hit the curb. That can happen in a turn to either side depending on the roadway. I've seen as many cars"clip" the road divider when turning as I have hit the curb by the sidewalk.

in the uk if you were doing a driving test ..and you done hand over hand ..you would fail ...its ok for racing drivers ..but for normal driving you pass the wheel through your hands ..

you answered your own question..

The hardest part is maintaining situational awareness - knowing what is on each side of you and behind you all the time, while predicting what drivers in a wide area ahead of you are going to do and watching out for pedestrians and hazards, all at the same time and constantly.

Nope, never had this problem. Are you trying to turn too early? Wait until you get the point where you need to turn and then do a HARD turn, not one of those slow gradual turns that I see people doing, which annoys me to death.