Uploading to Pixiv
Aspiring artists may want to actually put stuff up on pixiv, so here's your chance. Press the button that reads イラストの投稿 on the main page's navigation bar. This will take you to a very familiar upload bar. Images must be PNG, JPEG, or GIF. Browse for something and upload it.
The next page will be this:
Please note that I drew you all a very beautiful work of art in a minute on SAI just for this tutorial! Click the submit button when you've filled it out and you should be finished.