SSL redirection headache. Can you help, pls!

[bunnny]

hello friends, i'm not sure if i'm doing to the right place, so pls excuse if i'm mistaken.
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i just got this ssl certificate but i have some doubts how exactly should i config the whole magic. i create the secure.domain.com which suppose to be the sub-domain for the login page which means when user decide to sign up/login to immediately transfer to the ssl state(sample: see ebay.com and then their https login page). so, far the home page which is domain.com(or www.domain.com) it doesn't need to be covered by ssl. so, i was just wondering how do i play the game? i know it's kinda tricky and the key is somewhere in the sub-domain name(cP set up), .htaccess and/or index.php files but not very clear to me. i'd greatly appreciate your help! thanx

p.s. i tried to find some tips here but still confused...
(pls see the issue in my sig)