Trust me, your future self will thank you if you follow these few steps:
1. Start contributing to your Traditional 401-K NOW.
Ideally, you want to contribute as much as your company matches. For example, if your company matches up to 6%, you should contribute 6% of your paycheck. THAT IS FREE MONEY, HONEY. Also, your contribution will be 6% of your paycheck BEFORE tax, which ultimately means you lose less of your paycheck to Uncle Sam. You will pay taxes when you retire, but we will let your future self worry about that. This is a great resource: http://money.cnn.com/retirement/guide/401k_basics.moneymag/index4.htm
2. Generally, “target” retirement funds are simple investment strategies.
I am currently invested in a 2050 target trust which means I am targeting 2050 as my retirement year. Like obviously, I am going to like win the lottery and retire earlier than that, but just in case something goes awry… http://www.fool.com/retirement/general/2015/06/09/vanguard-target-retirement-fund-your-simple-path-t.aspx
3. If your company doesn’t offer a 401-K plan, create your own and invest in an IRA.
A Roth IRA is probably your best option at this point. You can only contribute up to $5,500 per year, but the money gets taxed going into the IRA so you won’t have to pay taxes when you take the money out, and the money you earn as the IRA grows is tax free. Here is a great resource to answer all your questions: http://www.rothira.com/what-is-a-Roth-IRA
4. A Roth IRA can also be used as a house fund.
I currently am invested in a Roth IRA because I can withdraw up to $10,000 without penalty to purchase my first house after 5 years of investment. More info on that: http://www.rothira.com/blog/should-i-use-a-roth-to-buy-a-house
If you start here, you will really starting off adulthood on a great foot.