Next we're going to put some clouds into our picture, start by selecting the eyedropper tool then pick a color from part of your render, you should now have a bright pinky color as your foreground color. Create a new layer, now select the brush tool then go into your clouds brush pack and choose a cloud brush. Now place your cloud somewhere over the girl then use the same masking technique we used for the line and for the renders but for this we want most of the cloud in front of her. Below I've shown what it should look like after you've added one cloud and masked it.
Now repeat the last step twice more, using a different brush and picking a different color. Remember to put it in a new layer and to mask it in the same way.
Now we're going to add a kind of glassy effect that we've been seeing a lot recently in this type of art. First create a new layer then select the polygonal lasso tool then draw a four sided shape similar to the one below.
Next select the brush tool and choose a 400px round brush, 0% hardness, 100% opacity then change the foreground color to white. Now just brush along, just outside the edge of the box to get this effect, you may need to try a few times to get it right. Now hit Ctrl+D to deselect then you can move or rotate this layer.
Now do these two steps twice again, but make the rectangle selection at a different angle or size, so you have three of these glassy things like in the image below.
Now alter the opacities of these three layer to something between about 20% and 35%, just until they look right and don't do them all the same opacity, make them different and it will add some depth.
In this step we're going to put in some random wee lines, this is quite subtle but it still adds to the overall image. First select a 1px round brush then choose a bright color, either yellow, orange or pink then brush some randowm lines in then do the same with a different color. Take a look at stage number one. Next add a layer mask by clicking the layer mask button at the bottom of the layers panel and use the second part of masking technique that I mentioned, where you blend the ends of the lines. don't worry about making these lines go behind the girl. You can see this in stage 2. Then just change the blend mode of this layer to color dodge, You can see what mine looked like in the bottom image, stage 3.
The next thing I did was to add some small dots, they aren't really visible in the image below but they do add to the image. Create a new layer then select the brush tool and choose a 1px soft round brush with full opacity. Make sure the foreground color is white then just put some dots on the page, try also doing some with a 2px brush as well.
That's us pretty much finished this tutorial but I did add a few finishing touches to the image and there is still a lot you could do to it. I added a very faint lens flare on a black layer then set it to screen then masked it a lot and lowered the opacity of it. I also put some white lines in to the right of the model and in a new layer then moved the layer to the bottom of the layer stack then masked it out a bit to blend it in. I then did some color adjustments to bring out the reds and some highlights, I used a mixture of Brightness/Contrast, Curves and Color Balance adjustment layers. Just experiment with some adjustment layers until it looks good. Have fun with it.