Erasing and formatting DVD-RW

[SilverBlade]

I was wondering, if you need to format an 'RW' disc before using it. Or should you write something onto the disc before you erase it?

I am asking this because this may be have damaged my drive since I erased an rw disc before writing, and then I can't use the disc

Here's my setup
Pioneer A05 original firmware
Nero
Maxell/Memorex/Pioneer/Optodisc DVD-RW's