Investing is important, but that doesn't make it any easier to find extra cash lying around, especially during the holiday shopping season.

So what do you do when you want to build wealth, but the holidays throw one expense after another at you?

Dr. Gail Saltz, author of The Power of Different suggests having the cash you intend to invest set aside before you get hit with the temptation to spend money -- not just on yourself, but also your friends and family.

"So when you see the pair of shoes or when you see that there are tickets to something you really want to go to - in the moment is when it's most difficult to observe willpower for delayed gratification," she said. "So really what you have to do is set this up ahead of time when you're not in your weak spot."

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