Wet sanding direction

[clemsonteg]

So I'm spraying epoxy primer (SPI) on my truck today (in between coats at the moment) and I can tell that I still need lots of practice and that I need to move faster. I have some runs that I will need to sand out. When wet sanding, do I follow the same X pattern method I used when block sanding, or do I go in a single direction? Are there any tricks to removing runs before sanding?