Kayla D. answered 19d
Computer Graphics | Digital Art | Anime | Animation | Blender
You can start putting a portfolio together when you start having a handful of your best finished work. Generally, I recommend considering what the goals are for the portfolio. For example, if you want to be a character illustrator, you'd want to include realistic and stylized illustrations, ideally fully rendered and colored with putting in a fair bit of practice. You would not want say still life or background pieces in a portfolio for character art since they would not be as relevant, unless they tie in with a story from another picture or serve some significant purpose. The timeframe is different for everyone, but generally, you can start putting together pieces after taking advanced drawing lessons and practice for at least half a year generally.