You may have seen the custom "skins" sold by Ebay seller eacoskins for Meizu M6 and M3s. He also makes skins based on any pictures that you provide.
I cooked up this photoshop template for designing and testing custom "skins" for the M6. It's a psd file so you just make a new layer somewhere in the middle of the stack, where I've provided a few samples, paste your new picture in, and then make sure that your picture is the only one made visible, along with layers 1 and 2 that make up the frame. Your picture should be about 500x290 for this test.
It's a little crude but it works great to get a better idea what your meizu will look like after you apply one of these kits.
Here's a hint when looking for great pictures: Search for Sony PSP wallpapers. They are about the right dimensions already, and people have poured tons of imagination into designing these, so the choices are astounding!
Here's the template!
Meizu M6 Skin
Template
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