If you are fortunate to accumulate savings and investments there is normally a point where it's wise to have an advisor. For many employed people they will tuck most of their savings into 401k's created by their employer. But many self employed people don't yet have such a plan but they are earning good incomes.
My rule of thumb is if someone crosses over $250k in savings you should be considering getting some help. You've heard of Certified Investment Advisors, they are "generally" a safe place to turn. They invest in their own training, go to seminars and try to become true professionals.
However there is no guarantee that because someone appears to have credentials that they will operate in a completely transparent, honest manner.
Most people start by asking friends or their accountant who is reputable? A CPA is likely to have numerous contacts and, more importantly, will have professional connections to investment advisors. Preferably they will deal with advisors on various levels to better understand whose judgment is sound, has been consistent and does not seem to have a tendency to go off track.
Who should you be more cautious about? Stock brokers are often more tempted to trade your account more aggressively because they receive fees for increased trading. A stock broker may be entirely appropriate if you have a percentage of your savings which you would like to more aggressively increase and you are willing to take bigger chances. There are also sales agents for a broad array of broker dealers. They are often selling investments which are not inside the stock market. Here again you may find tempting opportunities but offerings from the broker dealer sector can be more risky.