If you're a 30-something, you should have already started saving for retirement. But if you haven't, it's not too late. You can start today by socking away whatever you can set aside.

And for those who have been saving for retirement, that's great but now is the time to revisit your retirement savings strategies. Keep reading to learn more about the best ways to save for retirement when you're in your 30s.

Stockbrokers work for brokerage firms which generally fall into one of two categories: full service and discount brokers. Traditional, full service brokers advise clients about what to buy, provide market research and other services and execute stock trades. For their troubles, they charge hefty fees of hundreds or even thousands of dollars.

Discount brokers, however, simply execute the trades as required by law, and charge reduced fees. You'll get less specialized advice and intel on market movements though some discount brokers do provide free research. By using a discount broker, you're taking responsibility for your own investing and financial future.

Index funds take the guesswork and research out of that equation even for novice investors. Index funds are baskets of stocks that seek to mirror the performance of a given index, such as the Dow Jones industrial average, instead of trying to beat it.

With just a few well picked index funds, you can achieve global diversification across virtually all sectors. Index funds are passively managed, so they generally have very low fees. If you buy a fund that mirrors the Dow, for example, your fund gains or loses what the Dow gains or loses for as long as you hold the fund.

Exchange traded funds (ETFs) are funds that can be traded on an exchange the way stocks are bought and sold. Unlike mutual funds, this enables buyers to purchase or sell funds in shares during trading hours.

ETFs are a great way to buy index funds because they enable investors to buy in much smaller increments than what would be required to buy into a traditional mutual fund. And unlike traditional funds, they offer the flexibility of selling a portion when needed.

Now that you've opened an account with a discount broker, you'll have to figure out when and how to shift money into your index fund. Dollar cost averaging is a strategy that lets you roll with the ebb and flow of stock market gains and corrections.

By investing fixed sums of money over time on a regular basis without regard to the stock price, you avoid the pitfalls of trying to "time" the market which is a monumental task even for those with the time, capital and expertise. Dollar cost averaging doesn't require any of those attributes.

If you invest, say, $100 in your index fund on the 15th of every month, you will, on average, buy more shares when it's cheaper and fewer when it's more expensive which should be your goal anyway.

Acorns is an amazing app that works in the background to help you save and invest for retirement with nothing more than your spare change.

The app links to your debit and credit cards, and rounds up all of your transactions to the next dollar. Your spare change is diverted directly into a diversified portfolio of your choosing. Acorns suggests one of its portfolio templates based on your risk tolerance. Every portfolio is diversified with a mix of large, small, emerging and real estate stocks, as well as corporate and government bonds.

So, if you spend $1.40, Acorns rounds it up to $2 and puts 60 cents into your portfolio. Acorns doesn't charge minimum deposit requirements or take commissions for trades or rebalancing.

Many Americans rely on employer based 401ks for their retirements. But Roth IRAs are a great alternative retirement vehicle for people in their 30s, or supplementary, if your employer matches funds in a 401k.

Like 401ks and traditional IRAs, Roth IRAs let account holders save for retirement with tax benefits. Roth IRAs shelter after tax money from any further taxation, both while it grows and when it is harvested.

Roth IRAs come with a few great benefits, the biggest of all is that, unlike other retirement vehicles, you can withdraw from it without incurring a penalty.

If a Roth IRA is right for you, chances are you can set it up through your discount broker.

When you put money into a 401k or traditional IRA, there are steep penalties for early withdrawals. But now that you have a Roth IRA you have the security of knowing you can tap into it if an emergency arises.

Take your rainy day emergency fund which is probably collecting meager bank interest, and invest it into your tax free Roth IRA that you established with your discount broker. The maximum investment amount is currently $5,500. Now that money is collecting index fund interest and if you need it, it's there. The same can go for money you're saving for a home, for your kids' education or anything else substantial.

According to Kiplinger, people should revisit and adjust their insurance coverage in their 30s. Chances are pretty high that you didn't have a lot of assets to protect throughout much of your 20s. But in your 30s, you might have a home or other assets that could lead to catastrophic losses if they were underinsured or improperly insured. Hedging your bets with renters insurance could prevent a catastrophe.

If you add insurance with the same company you use for, say, car insurance, you may wind up breaking even or saving money. This was the case for 37-year-old Los Angeles resident, Robin Bell Albury, who saved money by bundling with GEICO.

"I already had car insurance with GEICO," Albury said. "When I added renters insurance the bundling lowered my car insurance premiums so it almost evened out."

Saving money is a matter of having money to save. Your 30s are a great time to downsize your lifestyle and rein in spending to free up money for your retirement fund. By implementing a few savings strategies you could possibly save thousands of dollars.

We all know to make coffee at home and to limit takeout and delivery. But technology can help you realize big savings right away. According to the NPD Group, the average cable bill was $86 in 2011. At one point in 2015, it was hovering around $123.

Until recently, cutting the cord meant real media sacrifice. Now, streaming services like Netflix, Hulu and Amazon Prime offer legitimate alternatives for just a few dollars a month. Supplement that with standalone services like HBO Go and live television apps like Sling TV, and you'll hardly miss your old TV service, you certainly won't miss the bill.

If you're in your 30s you should have started saving for retirement already. If you haven't, don't panic. It's quite possible that your prime earning years are still a decade or so away.

What you have to do now is simplify your investment strategy with simple, effective, low cost vehicles like index funds. Avoid throwing money out the window to full service brokers or fund managers. But most importantly, dial down your lifestyle and sacrifice amenities. It will all be worth it to watch your retirement savings grow.