Cyclists never turn left like cars. Instead: ride straight across the intersection, pull in at the far corner, re-orient your bike in the new direction, and ride on when the way is clear and you will not get in anyone's way. It is called the "Copenhagen left" (a box turn), and it is mandatory.
You are already past the stop line by then, so you are not obliged to wait for the crossing direction to go green - you go when there is room. Cutting diagonally across an intersection is both illegal and the easiest way to end up in front of a car.
Cyclists in Denmark never make a sweeping left turn across traffic like a car. Instead you make a two-stage "box" turn, the Copenhagen left: ride straight across the intersection on green, pull in and stop at the far right corner, and turn your bike to face the new direction. It is not optional - cutting diagonally across the middle is both illegal and the quickest way to end up in front of a turning car.
The second stage is the part visitors get wrong. The law says you complete the turn when it can be done without getting in the way of other traffic, so you set off as soon as the road in front of you is clear. You have already crossed the stop line, which means you are not required to sit and wait for the new direction to get a green light. Often the green arrives first and you simply move off with everyone else, but a clear road is enough on its own.
It feels slow the first time and completely natural by the third. The payoff is that you are never stranded in the centre of a junction waiting for a gap; you are always in a protected lane or waiting safely at a corner. Pair it with staying clear of truck blind spots and the big intersections stop feeling intimidating.