The kit stuff gets covered every couple of years on the Fans Forum.
The club gets to set broad rules (the kit will be blue & white halves, white on the left, no panel on the back etc).
The manufacturer comes up with a few designs (but often broadly matching the stylings for other clubs).
The club gets to chose from those designs
As an aside I know people seem to think that every last little decision is now made in Pune (or by SK), but the truth is, there are still good people left in various positions at the club wanting to do what's right. They may not have the power to influence the big stuff, but they still make sure their own stuff is done right and upholds the club's traditions and previous direction etc.