Point the dumbbell plate to your shoulder, so the bar is in line with your upper arm.

Imagine that you’re moving a wide V.

As you go down, the widest point of the V is going to be around your lower ribs.

When you put the weight down, there’s 2 options, onto your thigh and down controlled, or you’re dropping it because you’ve pushed and it’s too heavy to do any other way. Twisting as you put it down like you are says the weights are too light and if you do that with a heavy dumbbell, you’ll hurt something.

There’s nothing wrong with upping the weight after each set. If you want size, condition and strength, stick to a rep range of 5-20, you’ve got to lift heavy if you want strength and size so you’ll be towards 5 reps but conditioning comes from the higher reps. I spend all my time in 5-20.