how to take screenshot without pressing any button on my m31s

[siddhantgour]

By using tri finger gesture?

[SagarMaurya010]

use palm swipe to capture
available in motion and gesture settings

[Pukai1993]

you swipe on plan right to left.

[Sidhabhi]

Try these methods

one hand operation+

http://apps.samsung.com/appquery/appDetail.as?appId=com.samsung.android.sidegesturepad
or
Accessibility>Interaction and Dexterity>Assistant menu feature
or
palm swipe to capture(little tricky)

NOTE:: THERE IS NO THREE FINGER GESTURE SCREENSHOT OPTION IN SAMSUNG DEVICES

[Ehsank]

you have to press button brother or use gesture but this is not so useful
think you already enable assistant menu so use it for screen shot

[Ehsank]

go to settings >advance features >motions and gesture >enable palm swipe to capture