I would honestly suggest that you pick the institution and the fund (a target date fund), then explain why you did it. For people that age, the overwhelming part is not the saving so much as the "getting up to speed." It's a lot to ask of someone to research why they should choose x or y brokerage and x or y fund. Just open the thing and fund it, telling her that you'll help her in the ensuing years. My dad opened a Roth for me with $1,000 in it maybe 20 years ago. I've since changed the funds and disagree with his choice. But I would not have done it if he left it all to me to do.
This is a good idea. Young people, faced with too much information, are deer-in-headlights. (Hint: all people react the same way, young or old). Opening an account and funding the "base" of it, will give her a sense of surety; then the deal is, a match up to the annual limit. This will encourage her, unless she's got some money issues developing.
It's so hard for kids that age to save. It certainly was for me, and I'm a life-long saver! There is so much you "want" and the feeling of finally being "free" as an adult can bring on some unwise spending. So be supportive and encouraging, and yes, the video about compounding interest should be inspiring to her. Sit down with her sometime and show her the calculator site: https://www.investor.gov/additional-res ... calculator
Work through with her how much she will have if you and she "collaborate" for the next five (or ten) years in establishing the foundation for her retirement.
Good luck to you----and to her! Rus
I'd like to live as a poor man with lots of money. ~Pablo Picasso