Build an Online Store using BigCommerce

Hi, I am in process of creating my online store. It is relatively simple, selling only one product line. This product line has 28 different styles, with 2 different sizes per style. There will be at least 3 photos per style, plus carousel & album photos which need to be incorporated into site. There will need to be gift certificates and promotional codes, shopping cart, wish lists and payment gateways. In addition to products there will be standard info relating to shipping, privacy policy, terms and conditions, returns policy, sock information etc. I am using BigCommerce, so I need someone who is very experienced with this eCommerce platform, particularly knowing how to edit styles, editing fonts, adding/removing features, writing HTML etc. Initially, I need to ensure that the splash page is in place whilst the site is being constructed. Just something basic, incorporating a photo with the words "coming soon". I have written most of the content already and have begun transferring this into the relevant categories within BigCommerce. I have begun analysing what I like/don't like within the store thus far and have compiled notes on what needs to be changed.