The design process is fairly simple; got the brief, told what away colours to use (obviously home is red & white), set my templates up & off i went. Came up with half a dozen initial templates, then those are narrowed down, being constantly tweaked until all departments (retail, the manufacturer, the manager, senior players & the sponsors) are happy with the final designs. I believe Leighton is still the main man to sign things off cos he needs to have a decent product he can sell.
If I remember correctly the whole process took a couple of months, from start to finish.