You can sign up to Instagram using Facebook, your email address, or your phone number.
Obviously the Facebook option is preferable for Instagram, as the Facebook button is given more prominence.
We pick the phone/email option to sign up with. Phone is the default option here, but we switch the the email option using the tab in the header.
Now we add a photo, full name, and password.
It's now time to pick our username. No suggestion/default is given. We're told we can change our username at any time.
We're now asked to connect to Facebook to find friends. This can be skipped using a small "skip" button at the bottom.
Now we're prompted to search contacts for friends who are on Instagram. We can also skip this.
Now we are presented with a list of people to follow/hide.
We're now onboarded. When we land on the home page, we get a modal asking us to turn on notifications. Once we dismiss that, we're ready to explore the Instagram app.