What are you most proud of?
What advice would you give someone starting this project?
It's easier than you think.
What you will need
I used 4-ply sock yarn from Opal in green an black. But you can use any Acrylic yarn of similar weight or sock yarn. You need about 150 g of each color.
But as size is not important you can certainly also knit it with thicker yarn (then it will be quicker to knit :-)