
If you have come this far, it may be for two things. Either you know a lot about Android and you think we can tell you a new way to capture the screen, something that will not happen, or else you have no idea how to capture the screen with your mobile, in which case I recommend that you continue reading.
Screenshots
Your mobile has the ability to take screenshots. The big problem that exists is that the screen capture process is different in each of the smartphones, so we cannot generalize when talking about "How to take a screen capture". That is why you will find many posts that say "How to take a screenshot with the [Samsung Galaxy S6, or with the HTC One M9, or with the LG G5, or whatever mobile]". However, you have come this far because you do not know how to take a screenshot and we are going to try to tell you how to get a screenshot without having to look for the precise process for your mobile.

Volume + Off
In many mobiles, to capture the screen what you have to do is press the Volume Down buttons + Power off. Usually you have to keep these two buttons pressed until the screenshot is taken. You will see an animation on the screen that will confirm it, or a notification in which the screenshot will appear. However, it is possible that the process is also with the Volume Up button + the Off button. If your mobile is one of those that has a Home button, you should bear in mind that it may then be the Home button + volume up or down button, or Home button + Power off.
In any case, there are only a few possibilities to take a screenshot. If you have never taken a screen capture with your mobile, it may be somewhat more complex to find the procedure to follow to capture the screen. But in reality it is something generic, and the only thing that changes is the buttons and the time that you have to hold them down. However, it should not be too difficult to find how to capture a screen if you try the buttons on your mobile.