BigCommerce - New Header, Footer and Homepage Design

General information for the website: We sell beds and mattresses
Kind of development: Customization of existing website
Num. of web pages/modules: 1
Description of every page/module: Looking for a designer / developer with experience of BigCommerce to create for us a custom design for our web shop www.bedshopdirect.co.uk

We currently use the existing BigCommerce default theme but we need a custom theme created where the developer can develop a new website header / website footer and a new home page design
Description of requirements/features: The colour palette is fixed, used blue, yellow, white and black as per the logo.

website that we like are

http://www.cheapbedsdirect.co.uk/ (use of illustrations throughout the page)
http://www.happybeds.co.uk/ (content in the header)
https://www.mattressman.co.uk/ (colour palette)
https://www.mattresstomorrow.co.uk/ (footer we like)
CMS and Admin requirements: We would like a PSD design first, one / two rounds of design amends and then final build
Extra notes: