Use a round piping tip to make perfect round eyes
and for the black portions
use fondant instead of gel to make it perfect.
Fondant tools come in handy when you need to make the perfect shapes and designs.
To make your cake more realistic
add details like fur and make panda features bulky instead of putting flat fondant sheets.
Spray water often while you are working with fondant to keep it from drying out.
To secure the fondant sheets on one another
blend them using a moist cloth to make them stick together.