I've tried to hold down the home and power button, home and volume button, and also tried to swipe the screen.
None of these methods are working. Any ideas?
I have a Galaxy S6, not Edge, and I can take a screen shot by pressing the power button on the side, and at the same time pressing the home button. It's tricky to get the pressed simultaneously,and it takes 2-3 seconds, but I do get a screen shot.
If you want to use the palm swipe, it needs to be set in the Motions and Gestures area of settings, and I find that if I swipe with the edge of my hand rather than my palm, right to left or left to right, it works best.
There's another screenshot option... With Marshmallow, the Now On Tap feature (Hold the home button) takes a screenshot when you tap the Share icon.