It is recommended to save this one for when you've obtained Orochi if you're having a difficult time. If you're not having a difficult time, you should have no issue obtaining this achievement. As always, pick the character that you're the best with and do your best not to get hit. This should be incredibly easy with the aforesaid settings on the very first round. It only has to be one round, not the entire match.
Note: To make these easier, make sure that you do the following in the Options menu:
Set the difficulty to 1 (Easiest)
Set your players power gauge to MAX
Set your defence to level 8
Set CPU's defence to level 1