This is a very lengthy tutorial but it is very easy to create this effect.
1. Create a new document of any size. Change the background color to some dark color. I have used color #200c20. Don't use pure black.
2. You would have always typed a word or sentence continuously using type tool. But here to achieve the desired effect we are going to type each letter in a new layer. Select the type tool and type some text, so that each letter is in new layer. The font I have used is Franklin Gothic and I have typed 'Glow Girl'
3. Now we have to align all the texts there is a easiest method to do it. Select move tool. Move the first text(in my case 'G') where you want the text to start. Select all the text layers from the layer window.(Select the first text layer, hold down shift key and then select the last text layer in the layer window). Now move all the texts so that it is slightly overlapped one another.(Make sure that the all the bottom edges are aligned. If you are using mouse to move the letters then hold down the shift key while moving so that it stays aligned).
4. Create a new layer at top of all text layers. Create a white to transparent using Gradient tool, so that the white part stays at top of the work area. Make sure that the text falls on the faded part of the gradient.
5. Ctrl click the first text layer's thumbnail in the layer window and select the gradient layer. Press Ctrl+C to copy and then Ctrl+V to paste. A new layer will be created. Repeat this for all the letters.
6. Its better name all the copied layers so that it will be easy to work out further. Create a new layer. Ctrl click the first text layer(you will be getting a error message, ignore it) ad fill with some bright color in the newly created layer(make sure that the new layer is selected while filling the color). Change the blending mode to screen. Repeat this for all the letters with each letter with different colors.
7. Now if you are satisfied with the placement of letters you can merge it. Merge all the gradient layers by selecting them and pressing Ctrl+E. Then merge all the color layers by selecting them and pressing Ctrl+E.
8. Now duplicate the gradient text layer. Name it gradienttext2 and change the opacity to 15%. Again duplicate the gradient text layer with 100% opacity and change the name to gradienttextblur. This layer should be over gradienttext2. Go to Filter->Blur->Gaussian blur. I have set the radius to 2.2pixels. Again duplicate the gradient text layer with 100% opacity and change the name to gradienttextblur2. This layer should be over gradienttextblur. Go to Filter->Blur->Gaussian blur. Set the radius more now. I have set to 4.7pixels. Now your text appear as it is glowing.
9. Duplicate the colored text layer. Change the blending mode to opacity. Then go to Filter->Blur->Gaussian blur and set the radius to 1.2pixels.
Using erase tool select soft brush delete the lower part of the color text layer. Again duplicate the color text layer and change the blending options to linear dodge. Go to Filter->Blur->Motion blur. I have set the Angle to 90 degree and distance to 10pixels. Again duplicate the color text layer and change the blending mode to color dodge and apply motion blur. Set the distance to 25pixels.
10. Now merge all these layers. Duplicate the final layer and transform it so that it appears as reflection. Add layer mask and fill it with Black to white gradient. And reduce the opacity to 40%.
11. Create a new layer above the background layer. Using a bigger soft white brush and use it at centre of the text and change the blending option to overlay. Again create a new layer above the previous layer. Using a more bigger soft white brush and use it at centre of the text and change the blending option to overlay.
The final result.