For an electric circuit - Yes indeed, you would need to include battery power and a LED in your design.

If you want to get fancy you can use computers, sensors and transducers.

Look at Lilypads or Schemers for all of the exciting options.

Thanks for your comments philjam.

This is but one in a series of materials and methods I have posted in how to create conductive fabrics and threads. I use this 16 part series as a visual dictionary of conductive fabric and thread solutions lest I forget that sometime the best solution is the simplest of methods. 

Perhaps if you search on "conductive fabric", "conductive thread" or "clothing" you will find the information you seek?

I see your new to Instructables site Welcome to the Instrucatable community!  I hope you enjoy your time here.

Variety is the spice of life, yes?
We weight the pros and cons with every application chosen.

This is done only with black light reactive paints and photographed under blacklight. I can only imagine what could be created with LED's and this painting technique. Imagine the possibilities......