Warren Buffet's index fund investing strategy is to "set it and forget it" and not to get caught up in daily valuations. 
Don't think about owning stock if you aren't willing to hold it for then years. Buffet suggests looking at the big picture when you pick your investments.

Invest Long-Term

Warren Buffett advises against excessive borrowing, such as credit card debt or unnecessary loans. 
Some experts divide borrowing money into "good debt" and "bad debt."
<ul>
<li>Good debt is investing in your long-term future, such as a mortgage or student loan. Ideally, it should not have a negative impact on your finances.</li>
<li>Bad debt drains your finances with no prospect for future growth.</li>
</ul>

Borrow Wisely

Warren Buffet is known for his frugality. Frugality isn't about buying anything at a low price - it is about buying value at a low price.
The key is not just to look at the price, but to keep value in mind, too.

Price and Value are Not the Same Thing

"Long ago, Ben Graham taught me that 'Price is what you pay; value is what you get.' Whether we're talking about socks or stocks, I like buying quality merchandise when it is marked down."

According to Warren Buffet, if you invest in a very low-cost index fund over time, you'll do better than 90% of people who start investing at the same time. To start, Buffet advises to put 10% of the cash in short-term government bonds, and 90% in a very low-cost S&P 500 index fund.
The money you want to invest outside of your retirement accounts:
<ul>
<li>Learn some basic investing terminology.</li>
<li>Open a brokerage account.</li>
<li>Pick an index fund.</li>
<li>Buy the fund through your brokerage account.</li>
</ul>

Investing is Easier Than You Think

Prioritise your savings, not saving what is left after spending.
When budgeting, consider what is necessary to cover your basic needs, then figure out how much you want to save. The leftover is spending money. If it helps, think of your savings and investments as a monthly expense.

Pay Yourself First

Many people fall into bad money habits and don't realize it until their habits become hard to manage.
If you want to change your habit, start by breaking it down. Understand your cue, reward, and routine, then use it to break the cycle of your habit.

Don't Underestimate Your Money Habits

Trying to patch up financial issues that are causing you to live from paycheck to paycheck can keep the cycle going, such as payday loans, and hardship withdrawals from your retirement account. It may get you out of immediate trouble but will set you up for eventual failure.
<ul>
<li>Instead, consider looking for regular expenses you can trim.</li>
<li>Reevaluate your needs vs. wants.</li>
<li>Downgrade.</li>
<li>Learn some basic skills to deal with emergencies yourself.</li>
</ul>

Break the Paycheck to Paycheck Cycle

"Some material things make my life more enjoyable; many, however, would not. I like having an expensive private plane, but owning a half-dozen homes would be a burden. Too often, a vast collection of possessions ends up possessing its owner. The asset I most value, aside from health, is interesting, diverse, and long-standing friends."

WARREN BUFFETT

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High Value at a Low Price

WARREN BUFFETT

Myth: Cheaper Is Better