1. Make sure your mother really wants to live in the US. Like more than 6 months in a year, ideally 9 out of 12.
2. Make sure she understands she may need to stay in the US for a year or so to receive Green Card / Advance Parole.
3. If #1 and #2 is OK, file AOS packet as @Crazy Cat suggested.
4. If #1 is OK but #2 is not, file I-130 and go via consular processing.
5. If #1 is not OK, do not file for her Green Card. She will be able to come to the US using tourist visa. Just ensure she always goes back home on time.