There are two types of graphics: formative and summative.
Portfolios usually consist of formative work, creations that are completed and available for review.
Summative work is more difficult, because it demonstrates an acquired skill, rather than a finished item. Summative work is often used for authentication, proving that the person knows how and why to make things. The downside is that sheer technique may not obviously connect to useful work, and the artisan may not yet know which technique is preferable, or whether the technique should show in the finished work.
Summative work may also lend itself to experimentation, on the artisan or their environment, especially when proof can be subjective. Drill-and-practice has fallen by the wayside in some disciplines for precisely these reasons.
This image was formed from more than 150 screen shots, taken in three days. The composite took about three months (real time). The poster measures 14 inches by 24 inches, at 300 dpi. The thumbnail is 300 pixels by 175 pixels.
Most online games do not allow the user to make images of any size or quality; however, any artist with the time and the skill can circumvent that. This formative work is not original, but you can click here to view it.
There are times when learning how to do kit-making things is more important than the kit that results from the process. This following video contains items that demonstrate skill instead of product.
The premise of this short film is that an animator has a newspaper for the weekend, and decides to make a living room.
This demonstrates how to create a room from easily-available graphics. The work focuses on the assembly process, rather than the beauty of the art. The technique is primarily cut and paste, using Photoshop and a scanner. The pieces must be sized to the screen and perspective must be applied, so that the overall effect is a room rather than a collection of images. Texture and patterns are used for wallpaper, similar to some animated cartoons. Making the room more believable would require shadows, light sources, and highlights.
The movie was made with Movie Maker; the music is by Mozart.