"You can't always get what you want... but if you try sometimes, you might get what you need."
- Rolling Stones
You haven't left college and want to retire in 10 years. Rather than focus on getting something you want on your time frame, focus on the habits that will get you closer to your goal. It's hard to focus for 3,600 days in a row on a 10 year goal, so you should break it down into smaller goals. Also, you lack data - will all $40,000 go to savings, or will you need to pay rent and taxes? So focus on good habits or shorter term goals for now, starting with what you can do with $17,000 / year income.
Are you incurring student debt? What interest rate will you be paying? When you have debt, that establishes your base line value of money. If bonds are paying 2% (taxable) but your student loans cost you 4%, then you should take the 4% risk free return by paying down the loan (which means no more interest payments on the amount you paid off, which is where the 4% comes from).
Do you have an emergency fund? Finding a place to rent before you have a job may be challenging, and you might need to put up more than a month's rent. An emergency fund can tide you over while you find a job, but an emergency fund needs to be in cash.
You have the right idea saving in a Roth IRA. It should be hard to make a mistake at Vanguard, but aim for low cost index funds. Things like Total Stock Market, or Target Retirement will work well for starters. Besides the Roth IRA, you can save in a taxable account.
So overall, check your student debt interest rate, build up an emergency fund, max the Roth IRA, save in taxable... and aim for low cost index funds. When your situation changes, then you analyze your new situation with the new information (like rent and taxes on a $40k income).