I’ve had a few questions like this on http://www.flickr.com/photos/mindileatham so I thought I’d post the answer here:

Hi!
I’m Bharath Kishore, also a Paper-craft enthusiast. I came across your “Mermaid” made with water color paper. I’m very
impressed by the neatness of the cuts made along the curves small and
large. I would like to know if you use any technique or special cutter
that helps you, so that I can make some of my own cut-outs. Thank you in advance.
Regards,
Bharath Kishore

Sharp blades make a big difference! I like to use Fiskars Softgrip scissors and often sharpen them with a Fiskars sharpener. I personally prefer scissors to an exacto (unless I’m working on something very tiny) and when I cut I turn the paper more than I move my scissor hand.

Here’s what I’m working on today: