Squeeze page and mailchimp

hi guys, so i have downloaded many squeezes pages and i want to integrate them with my mailchimp sign up form account, but when i replace the action=something code and make it loook like action=my mailchimp signup form it leads me to the mailchimp sign up form, but when i replace the whole <form>..</form> code it gives me a crapy signup form design, so if anyone could help to make when the subscribers enter their emails it goes directly to the list and redirecting the thank you page instead of the sign up form without losing the squeeze page design.