Help creating custom iphone lockscreen keypad

[AWil1026]

I need help trying to make a custom iphone lockscreen keypad.I've downloaded templates from here but every time i import them into photoshop it looks different like it has no background. I wanted to know how would i get started on making the keypad? Do i need to make the buttons individual layers or can they just be one layer? I attached the files that i downloaded. Any help would be appreciated.