Hello. I have a friend on SSI, SSID. Her guardian on gives her about $430/mo., NO health insurance, living at a shelter. How to become her guardian?

I always try solutions that are easiest and quickest for a solution. If your concern is that the guardian isn't doing right by your friend, I think the first step is to contact the guardian and see if you can't nicely convince them to make some changes.  If the guardian is subject to any type of oversight, either by an employer, or the court (and usually the court is involved) you could bring your concerns to the attention of someone else if your direct contact with the guardian fails.  The last resort would be to petition the court to remove the guardian and replace with you.  You'd have to prove the the guardian wasn't doing their job and that you're a better fit for the job than another professional guardian.  The legal proceeding will be costly (expect no less than $5,000 and very likely more) and you'll have to pay that from your pocket.  If you are successful you may be able to recover that money from your friend's assets, if there are any.