Traditionally, we are used to press home and power button" simultaneously to take a screenshot. Ever Since home button is disappeared, tradition has slightly changed.
- Press and hold the Power and Volume down ( instead of home button) buttons simultaneously.
- Keep holding buttons, until you won't get either a flash, a sound or a vibration ( Make sure sound is enabled to listen sound ).
- Now go to Gallery > Screenshots, and share screenshot with your friends.
These steps are also working with J1, J2, J5 and J7.