Question: I bought a 240 GB SSD to replace the 500 GB primary HDD in my new MacBook Pro.

How do I clone the current Lion system image on my 500 GB HDD to the SSD? I want to clone the entire drive not just copy data.

I can only have either the HDD or SSD in the MacBook Pro at a time. I have an external 500 GB USB drive that can I use if necessary. I've seen suggestions on using Carbon Copy Cloner but I'm not sure how to proceed with only one disk in the MacBook Pro at a time.

Answer: 
SuperDuper <http://www.shirt-pocket.com/SuperDuper> is also an awesome back-up product and can easily clone a drive making a bootable backup. You can use it for free for what you're trying to do, but it's worth every penny for the extra features.
Use [Carbon Copy Cloner (CCC)](http://www.bombich.com/), I have used it in the past, it's great and free!
There is support on the website and tutorial videos.