Since I had no idea how to make a neon effect, I, as always, started the search. Among those simulating the neon effect I ran into this simple tutorial that allows you to Make the object glow.
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I did learn the technique and found it really useful while making this Christmas tree.
See how the decorations glow? Nice, huh?
If you'd like to learn how to make such a tree – you are welcome to go to this Making of a Christmas tree tutorial.
Have fun :)