The PSD file is setup at 1275px x 1875px (4×6” with .25” bleeds) CMYK 300DPI
The PSD file is very well organized, with color coded groups and layers named appropriately.The main folders that will require most customization are highlighted in different colors.
I HIGHLY suggest to familiarize yourself with what folders do what, is to quickly go down the layer list and turn off/on the visibility for the folders to see how that group affects the design.This should increase your work flow knowing what each particular folder does!!
Please experiment by turning folders off and layers because you can create several unique looks.