Have you been doing any investing lately? If not, you should be. Despite the market’s ups and downs in recent years, it’s still a far better place for your money than under the mattress. But (and here’s the catch) only if you do it right. As it turns out, a lot of Canadians are making some serious – and costly - mistakes. In fact, they’re all laid out in gruesome statistical detail in the Canadian Securities Administrators’ recently released 2012 CSA Investor Index.So what are so many of us doing wrong? Check out the biggest mistakes Canadian investors are making now.1) Not having a planNot everyone is a Type A overachiever when it comes to planning – we get that. But although you may have success with “winging it” in other areas of your life, investing without a plan is unlikely to lead to unexpected adventure – at least not the kind you can brag about at a cocktail party.According to the CSA Investor Index, only three in 10 Canadians reported having a formal, written investment plan. That’s up from last year, but we think you can do better. Actually, you have to do better, because the only way to take the emotion out of investing (read: stupid, spur-of-the-moment choices) is to make informed decisions, write them down and follow them like the law.Don’t make this mistake: Planting the seeds that’ll grow into a portfolio that will protect you for the long term takes forethought and planning. You can wing it if you want, but the results will be unpredictable, at best.2) Not knowing what you’re doingWhat do you know about diversification, compound interest and investment risk? If you’re like most of the Canadians the CSA surveyed, the answer is not nearly enough. These were the types of questions given to the survey respondents as a test of investment knowledge. Forty percent of respondents failed to even get a passing score.Don’t make this mistake: Knowledge is power. In fact, those who got the highest scores for investment knowledge were way more likely to do a background check on their advisor and have a formal investment plan. In other words, correcting this one mistake will give you a leg up on avoiding many other common blunders. Asking questions, taking the time to examine your investments and portfolio, and reading up on investing and personal finance (like you’re doing now) are the keys to getting it right.3) Having unrealistic expectationsWhat kind of return on investment do you think is reasonable? According to the CSA, if you had a fairly typical (and conservative) portfolio of Treasury bills, Canadian bonds and the TSX Index, your nominal rate of return (before taxes and fees) over the past five years would be right around four percent. Only 12 percent of Canadians surveyed got close to a reasonable estimate for returns on an average portfolio, while 29 percent had an unrealistic answer, and nearly 60 percent had no idea what a reasonable return would even be.Don’t make this mistake: Investing is all about balancing risk with potential return. If you don’t know what’s on one side of the scale, how are you going to make an informed decision about the other? You can get a sense of what’s reasonable for the markets these days staying up to date on financial news, and staying on top of your own portfolio. Because while understanding what an average return should be is handy, knowing what your returns actually are is crucial.4) Falling for fraud – or failing to report itWherever there’s money, there’s likely going to be some monkey business. According to the 2012 CSA Investor Index, more than one-quarter of Canadians believe they’ve been approached about a fraudulent investment “opportunity” at some point in their lives. But while less than 5 percent of investors reported falling for a scam, the consequences were costly - more than half of those unlucky few lost every penny of their investment. Astonishingly, 69 percent of Canadians said that reporting the problem is just too much trouble, and only 30 percent who were faced with fraud actually did so.Don’t make this mistake: The markets are fast-moving and quick to change, so beware of anyone who says otherwise or offers a guaranteed return. Get informed, ask questions and don’t be afraid to demand clear answers. And if you come across a “once in a lifetime” investment that sounds too good to pass up, consider doing just that – and reporting it to your provincial securities regulator.5) Failing to research and choose an advisor carefullyA financial advisor can be a great resource for investors, and there are tons of savvy and skilled advisors across Canada. But just because someone labels themselves as a professional doesn’t mean you have to take everything they say at face value. Unfortunately, while nearly half of Canadians employ a financial advisor, a full 60 percent of this group hasn’t bothered to vet the professional they’re entrusting with their money. Big mistake, especially since that information is publicly available (though you may have to do a little digging).Don’t make this mistake: An advisor’s professionalism and expertise can take your portfolio to the next level, so put some time and effort into ensuring that the one you choose has the qualifications and background you expect. When selecting an advisor, ask questions and do a background check. Where you go for this type of information depends on what type of securities the advisor sells. For financial advisors, check with the Canadian Securities Administrators and/or your provincial securities regulator. You may also be able to find information about an advisor (as well as potential disciplinary actions against him or her) at the Investment Industry Regulatory Organization of Canada. If you’re working with a professional who sells mutual funds, check the Mutual Fund Dealers Association of Canada. (Unless you’re in Ontario, in which case you need to check with the Ontario Securities Commission.) The reality is that most advisors are honest, hard-working professionals. But why not find that out the easy way?An investment in yourselfInvesting isn’t rocket science, though it does require discipline and engagement. Indeed, the key to avoiding the biggest investing mistakes is simple: invest in your own financial knowledge. Oh, and one more thing - pay attention. Mistakes are part of investing, but smart investors never make the same ones twice.