I made PSD and then got it approved from the client which i later converted into responsive html.
As the client needed a fully responsive wordpress theme , i then converted it to wordpress theme with mailchimp integration.
The MAILCHIMP INTEGRATION was done using the API of mailchimp and not by using any plugin.This helped in getting faster loading time.
The HTML was done using BOOTSTRAP.
The basic concept was to record emails of the visitors interested in the objective of the website by providing eye catchy design and user friendly interface.