[spinlock]

With your companies 401k or equivalent. Just put whatever percentage you want into a low cost, broad index fund. The most important part is to make this allocation before your paycheck gets cut (i.e. you never see the money).

[yummyfajitas]

Also make sure to change jobs every few years so you can move money from the 401k to an IRA without a tax hit. 401k's tend to suck - high fees, low returns, little competition. Most of the funds in your 401k are there because a fund salesman took an HR person out to a steak dinner.

When you change jobs, always move the 401k into an IRA and put the money into low cost ETFs.

[cdjk]

Unless you have enough income to be over the Roth IRA contribution limits and want to make yearly backdoor Roth IRA contributions (non-deductible traditional contribution followed by a rollover to a Roth IRA). If you have a traditional IRA there can be some tax complications due to the pro-rata rule. If any traditional contributions are instead in a 401k the conversion is a lot simpler, and tax-free.

The other way around it is to open an individual 401k if you have any self-employment income, but that involves a bit more paperwork than an IRA.

[melvinmt]

> you never see the money

Also important to add, if you invest with 401k/IRA money, if you don't want to pay a lot of taxes or early withdrawal fees, you won't "see" the money until you retire.

[aepearson]

What about someone like me with no 401k?

[kasey_junk]

IRA or equivalent. If you have no option for a tax advantaged account, the advice to pick a broad unmanaged index fund or etf still holds.