I started off with a base coat (O.P.I - Original Nail Envy Nail Strengthener), then applied one thick coat of China Glaze's Cross Iron 360 from their Ski Collection. (This colour alone was perfect for autumn, but of course I was going for a more Halloween inspired look.) I then used a black polish to create the French tip (Anna Sui - 024). Finally, I applied one coat of glow-in-the-dark nail polish (O.P.I - Zom-body To Love) on top of the black tip. Now the tip becomes a dark green to black colour. I finished off with a top coat (Sally Hansen - Mega Shine).
Here's a recap of all the products I used:
O.P.I - Original Nail Envy Nail Strengthener (http://x.opi.com/trNenvy.asp)
China Glaze - Cross Iron 360 (http://www.chinaglaze.com/try-me/)
Anna Sui - 024
O.P.I - Zom-body To Love
Sally Hansen - Mega Shine Extended Wear Top Coat (http://sallyhansen.com/products/nails/nail-care/mega-shine)
Nicole by O.P.I - Drying Drops (http://www.nicolebyopi.com/products/drying-drops)