Here's what I do, with all amounts yearly.
403(b) and 457 ($36,000, pre-tax)
Back door Roth ($5500, after tax with earnings tax-free)
US Savings Bonds, EE and I-bonds ($20,000, after tax with earnings tax-deferred)
Brokerage Account (variable amount, taxable)
529 Plans (~$8500/year, after tax with earnings tax-free if used for approved purposes)
Your friend should consider consulting a fee-only certified financial planner, especially if she isn't very knowledgeable about managing money, or she doesn't have a good handle on what her financial goals are. It's hard to give someone advice in the latter case especially, because choosing the best "tools" for a job depends on what she wants to use them to build.