Come back with nebula stock. I copy a part from this image and move it into our main picture, transform it ( use Cmd/Ctrl+T and Warp Tool – choose Edit-Transform-Warp) as shown below:
Lower opacity to 50% and use layer mask to remove rough edges:
Name this layer as “galaxy center”. Add an adjustment layer for this part with Clipping Mask to create a suitable color for the rest of galaxy ( look at step 3 if you forgot how to make a layer with Clipping Mask).
Go to Layer-New Adjustment Layer-Curves:
Extract spaceship and place it near foreground and downsize it :
Call it “spaceship 1”. Duplicate this ship three time, transform and resize them into different movements. Position them at two edges of picture and name them from “spaceship 2” to “spaceship 4”:
Make group for all spaceship ones. For spaceship 1 I add a layer with Clipping Mask and use soft black brush to paint on its bottom to darken it. Put the mode as Soft Light 100%:
Make a Color Balance layer within this group to change spaceships color:
I aim to make the main light source come from galaxy so the spaceships must get some reflected light from it. I add light for them by Inner Shadow effect. Right click each spaceship layer, choose Blending Options:
Pay attention to directions and light opacity as these spaceships have different positions and distances from the light source.
This is result we have:
Make a new layer within spaceships group. Use soft white brush to paint on the top of spaceship 2 and 3 as I think they need to be a bit brighter. Put the mode as Soft Light 50%:
As asteroid stock has a transparent background so you just need to use Move Tool to drag it into our canvas. I duplicate it three times, resize and transform them into different movements, and place at two edges of picture. To get rid of the same look I add layer mask for some asteroid layers and use hard black brush ( hardness about 90-95%) to erase some asteroids ( don’t use soft brush as it will leave a soft unatural edges):
I add Inner Shadow for each asteroid layer to create some light for them:
Make group for these asteroid layers. The asteroids still look too dark so for each asteroid layer, I add a Brightness/Contrast layer ( Clipping Mask) to reduce their contrast:
Create a Curves layer within asteroid group to change their color:
In next steps we’ll make spaceship trails. Make a new layer on the top. Use Polygonal Lasso Tool to make a selection at the bottom of spaceship 1 as shown below and set feather for it as 3:
Fill this selection with color #81cafa then use layer mask or eraser to get a similar look below:
Duplicate it three times and position them at the bottom of other spaceships, remember to change the size and direction to fit these spaceship ones.
Call these layers from “trail 1” to “trail 4”.
Make a new layer and use soft brush with same color (#81cafa ). Paint in the center of these trails and change the mode to Overlay 100%:
Continue with a new layer and use soft white brush with small size to paint like below and set the mode as Overlay 100%:
New layer again and use soft white brush with larger size to make a glowing effect at the spaceship trails. Lower opacity to 50%: