Security messures: cookies

Having dealt with a suspected session hijacking lately, I have been doing some research and came across this article:

Get the Best Practices Guide

To summarise, it recommends 12 security measures. I was wondering how many of these were really necessary. My site is basically just a blog, not some commercial site.

I am sure https: and a Security Certificate are advisable, but what about the other steps. Are any/all of these worthwhile for a site like mine?

• Use the Secure Cookie Flag
• Use Long and Random session IDs
• Regenerate Session ID after login
• Perform Seecondary Checks
• Change the Cookie Value
• Only Accept server-Generated Session IDs
• Do not accept session IDS from GET/POST Variables
• Time out inactive sessions
• Destroy suspiious referrers

The page I need help with: [log in to see the link]