Please find attached files which talks about how to configure SSL for SM. Please note the configuration guide talks about configuring SSL for both windows client and webclient and you can look out on how to configure SSL only for webtier.
The configuration of SSL is mandatory for 9.30 and the procedure is different for that from version 7.0x. Much of the information is in the online help for SM. The only 9.30-specific whitepaper I can locate is attached below. It covers configuration of Trusted Sign-on and LWSSO between the HP applications, but may also be helpful in configuring web tier.
You said "I have to enabe SSL..only for Web client ..to use https url for sm logins."
To be clear - if you want web users to use "https", you're enabling SSL between the browser and the web server. If web users can use "http", and you only want SSL between the web server and the service manager server, that's another configuration entirely.
Which configuration (if not both) are you looking to implement? If you're looking to do SSL only between the web server and the service manager server, and the use of "http" is okay, then the guidance and documentation already provided in this thread will get you there.