Self-made millionaire Steve Siebold says that building wealth is a learnable skill. If you work at it, you can improve. "Like most things in life, becoming good at attracting money is no different than becoming good at anything else, be it being a sub-par golfer, losing weight or mastering a second language," he writes in "How Rich People Think." For most people, wealth, like fluency in another language, doesn't simply come to you one day. Getting rich takes sustained work. Here are six lifestyle changes that have worked for self-made millionaires and billionaires and could also work for you.

Ditch the steady paycheck

Siebold, who spent decades studying the world's wealthiest people, says the rich are typically self-employed, while average people tend to settle for steadier situations. "It's not that there aren't world-class performers who punch a time clock for a paycheck, but for most this is the slowest path to prosperity, promoted as the safest," he writes in "How Rich People Think." "The great ones know self-employment is the fastest road to wealth." That's not to say you should quit your day job right now. In fact, self-made millionaire Daymond John says the idea that you have to quit your 9-to-5 to become a successful entrepreneur "is garbage." Instead, start something on the side, says John, who lived on the tips he made waiting tables at Red Lobster while launching the clothing line that would evolve into a $6 billion brand.

Get used to being uncomfortable

Negotiate your salary

Sure, negotiation can be a tricky business, but not getting paid what you're worth could mean the difference between an average life and a rich one. After all, as self-made millionaire Grant Sabatier says, "the number one thing that will dictate your future earning potential and get you to $1 million the fastest is how much money you are being paid today." Before asking for a raise, do your homework. Read up on costly negotiation mistakes, negotiation tips and career expert Suzy Welch's top advice.

Don't show off — show up

"I didn't buy my first luxury watch or car until my businesses and investments were producing multiple secure flows of income," writes self-made millionaire Grant Cardone, who was struggling to make ends meet before hitting seven figures. "I was still driving a Toyota Camry when I had become a millionaire. Be known for your work ethic, not the trinkets that you buy." Warren Buffett may live by a similar philosophy. After all, the legendary investor prefers to eat at McDonald's and never spends more than $3.17 on a breakfast sandwich.

Be willing to use other people's money

Rich people aren't afraid to ask for funding. If they come up with a great idea they're unable to finance, they "proceed to use other people's money to make it happen," Siebold writes. "Rich people know not being solvent enough to personally afford something is not relevant. The real question is, 'Is this worth buying, investing in, or pursuing?' If so, the wealthy know money is always available because rich people are always looking for great investments and superior performers to make those investments profitable." It's worked for filmmaker and self-made millionaire Spike Lee. "I've got no problem asking people for money. Because I believe. I believe in my talents, my storytelling abilities and also the people I surround myself with on the projects that I make," he tells online investing service Wealthsimple.

Take risks and be willing to make mistakes