Well, you will have to buy a screen at AliExpress and replace it. Your picture is not very clear, but did you drop it, looks like it is damaged at the bottom.
I cannot give you a direct link, somehow I have to login on Aliexpress before I can search.
Ebay link: http://www.ebay.com/itm/Black-5-36-Meizu-MX4-LCD-Display-Touch-Screen-Digitizer-Assembly-Replacement-/291285011409
For repair guides, use the search option or Google.