Design a watch strap builder for UNDONE

UNDONE

UNDONE is a company offering customized watches. Through our website you can literally create your unique watches, choosing the dial, bezel, hands, case, strap with a wide selection of options that create up to over 1 million combinations.
For this project, we want to develop a new concept, called UNDONE STRAP. We will offer cool looking straps compatible with Apple Watch and other watch brands (not only UNDONE watches) that can also be customized with a print/monogram/initials.
UNDONE strap will likely be hosted on a different website or anyway have a different positioning compared to UNDONE watches since UNDONE straps also offer solutions for other watch brands.

VERY IMPORTANT:

This project is for UNDONE Strap, a product that is different from our UNDONE Watches. UNDONE Strap allows to choose a strap and customize it, for any watch out there, with a focus on Apple watch. That means that we do not have to sell UNDONE watches here, but instead explain the concept of a customizable strap, compatible with the watch you have. The target audience is mostly apple watch users, but also people wearing other watches (not UNDONE).

http://www.undone.com

It must be clean, cool, modern, intuitive and the user has to be guided step by step.

2 pages:
1) The first page is a landing page with a CTA linking to the second page.
In this landing page we need to introduce the concept of choosing a strap for the type of watch you want and the fact that you can actually customize it, choosing the print/monogram/initials to print on. Remember that we are not selling UNDONE watches, but straps compatible with Apple watch and other brands, that is possible to customize.

2) The second page, that we name the strap builder, represents the tool that allows choosing the watch and the strap. It is very important to keep UX in mind and guide the user through the steps needed to find his strap.
Ideally the steps would be (but you can change the structure if needed)

1) Choose your watch brand
2) Select the watch model
3) Choose the strap color
4) Customize options (initials, print selection, monogram)

The user should also be able to choose the buckle for the strap (since buckle and strap color have to look nice together). We haven't reported this step because we don't know where to pull that in without overcomplicating the process.

It is of key importance to have a mobile-friendly version, as the majority of the traffic will be coming from social media using a smartphone.

again, to summarize, we need 2 pages:
1) Homepage/landing explaining this concept. the CTA has to take to the 2nd page.
2) Strap builder, which is the tool to select your watch brand, select your strap and customize it.

Generally we prefer a bright UI, but we are open to ideas.

IMPORTANT:
we are not selling UNDONE watches. This is a watch strap concept, where you can buy a strap for your apple watch (and other brands) and customize it.

UX
UX
UX
For both pages.
The Landing page will have to explain the concept, keeping a fresh and young positioning.
The strap builder has to be product visual-centric, to see how the final product looks on the watch. It is extremely important to also have a nice and clean selection flow.