Okey, now im going to make a tut on how to make neons and neon tubes. Sorry if my english is bad :-/
First of all you have to open the pic of the car u want neons on. I've choosed to use this volvo:
First of all you have to select the area where you want the neons to be with the Polygon lasso tool(L), and when you have done that u have to right click the selection and set the Feather Radius to 12-15.( I used 13):
Now make a new layer(Ctrl+Shift+N) and fill it with the colour you want the neons to be:
Okey....now Its time to make the Neon tubes. Selevt the Line tool(U) and choose the colour u want the tubes to be. Make sure u have the same setting as I use. Then just draw a line where u want the tubes to be:
To make sure the tube looks realistic u have to add some shadow to it using the Brun Tool(O). And after that open Blending Options:
Now u have to add some glow to the tubes, and here is the part we are going to use Blending options. Make sure u have the same setting as I have(if u have red neons u have to choose red where I choosed blue at blending options, and if u have yellow u have to choose yellow colour etc):
Here u have the result: