If I were you, I would put the process on hold until you finish graduate school before you start. It is true than VFIAX requires a $3,000 initial deposit. What you are going to need to do is to just save your money to you get to the $3,000 and then open the account. Look at Vanguard VGSTX which has only a $1,000 to start but you will want to switch when it gets to $3,000 in order to get a better rate.
When you get a job, have your Human Resource Department withdraw $750.00 from you pay and send the money to Vanguard. The HR department will know how to do this.
Save something, $500.00 per month will produce $1,000,000. Maybe later you can up the amount.
My starting salary was only $13,000 when I arrive at Alabama in 1969. I have increased considerably the amount I deposit as my income increased.
From Warren Buffett: https://www.youtube.com/watch?v=pPyqNXC5MzY
