Hiya Will

Actually, this could be a hardware Q
But if you want to make a software raid'd drive, you will need to partition atleast 2
drives as dynamic, then you can turn them into spanned/striped.
Or, if you are referring to hard-ware raid, you will need :
1 - Raid ctrl.
2 - 2 or more harddrives
3 - Driver for the above ctrl.
4 - Time to think... do you want RAID 0, 1, 5 ?
5 - Next input :P