Organizing user home directory between SSD and HDD
You can use aliases for those directories containing lots of data. Example:

/Users/you/Movies -&gt; /Volumes/MyStuff/Movies
/Users/you/Music -&gt; /Volumes/MyStuff/Music
/Users/you/Pictures -&gt; /Volumes/MyStuff/Pictures


The easiest way to wipe the contents of the previous drive is to open Disk Utility, select your drive, and then select the 'Erase' tab. Choose the options you want and wait until it finishes.