Computer or non mobile site for both avatar and sig.
When you get to one of those then you click on the green "my bump" and it may ask you to log in. Then toward the top left side above your avatar you'll see "edit avatar" or something similar and you can upload or change it.
If you want to change or create a signature you'll have to do that from a different location. You'll click on the little grey head on the upper right hand corner and under you avatar picture you'll see edit signature settings and you can change it from there...hope that helps!
~Missed MC at 8 weeks. D&C at 12 weeks on 4/17/13~
Re: How to change avatar