If you want a custom image for your ship, view the ship in your inventory, you'll notice
a checkbox to the left of your ship, hover you mouse over and write down or remember the number that pops up.
Then click on the number of CPs you have, find and click "Exchange CPs".
Scroll down to the custom image section, then select "Ship" on the dropdown menu.
Fill in all the other fields and click "Exchange".
You can either use a public custom image or a private custom image, if you don't like any of the public customs I'll make you a custom image if you'd like.