Anyone can participate, even after the April 6 start date. For instructions, see https://thegreatdiscontent.com/100days.
Committing to making and posting something every day is one of the best hacks that any artist can introduce to their art-making process. Whenever I've committed to similar things, I've noticed rapid improvements in my own art.
There are other similar projects, such as Give It 100 and Illustration Friday. If you hear of any more good ones, let me know about them in the comments below.
