Your Instagram profile photo should have an aspect ratio of 1:1. This means it should be at least 110x110 pixels. If you're using a desktop version, your best bet is to use an image cropper to change it to a square or even a rectangle. Note, however, that the image size is limited to 10 MB. You can still take the picture with the Photos app. If you upload a picture from your phone to your profile from your phone, you must include it in a square before it is uploaded to the app.