Whenever you complete or save an image that you have worked on, it will get stored within the Album option of the game. Following from the game's narrative, the images you created are stored as images on TCG style cards. From here, you can select the card you wish and do a variety of things with it

The first notable feature is a slideshow. This shows off all of your saved artwork piece by piece. However, when you select the top left item on the bottom screen, you unlock a variety of features.

Here, you can edit the image in a multitude of ways. The first option of note is the ability to change the type of card that your image is. This is especially useful if you created an image in Free Paint mode, as it doesn't automatically save a type. The rest of the options are as follows

Edit: This allows for you to edit the image. It brings you back into Free Paint mode, using the image you have selected. This allows for you to gradually work on a piece of art.
Share: This option allows you to share your image, giving you the options to share via Miiverse, or by using the local wireless of the Nintendo 3DS
Delete: This will delete the image
Save as JPG: This will save the image onto your SD card as a 1024x768 JPG image.
Name: This allows you to set the name of your card. This can be anything at all, and is not limited to the Pokémon's name.