It's like using a smart piece of paper that just gets out of your way and let's you create, assign, toggle, set dates, etc really intuitively.
I'm a freelancer - and for my usage I typically have a Workspace called Freelance Projects. In that workspace I have many projects, each for each freelance gig I land. I then invite my client (YOU CAN INVITE UP TO 30 PEOPLE PER PROJECT FOR FREE HOLY BALLS) and collaborate intuitively from there.
He/she can upload photoshop files, images, text files, edit desriptions and I can comment on them and we go back and forth. Better than email.
I used to procrastinate a lot. It was my achille's heel; but since Asana I enjoy working because there's something deeply psychological in ticking things off and seeing them grayed out.
If you haven't checked it out.
There's also Trello but I kind of dislike it when there are more than 5 items in a list. It gets unwiedly.