I had a similar experience in late 2012, after the sale of software. We immediately invested the money in early 2013 with a reputable financial advisor and got a 24% return last calendar year.
Then, this year, my wife and I decided to purchase some buy and hold rental houses as a way to diversify. Don't dump all your money into real estate.
The one issue I'm having is that having cash doesn't necessarily make you attractive to lenders.
Even though our money, for the most part is in taxable brokerage accounts, reaching out to lenders for rental property loans...they mostly have looked at our W2 income on the past 2 years. We refied our primary home with a 10 year mortgage in hopes of paying off before our 1st child goes to college.
That's the only debt we have and still our debt to income ratio was "too high" to purchase additional rental property.
I own my own business, and typically reduce my W2 income as much as possible, but that has hurt me....even with having access to cash.
So...you may want to start small, but you need to start soon....especially if before you new cash that you had a regular paying W2 job.
One thing I did was to partner with another person who had a very low DTI ratio and we did a 75/25 LLC, where I would pay 75% of down payments on the rentals we purchased. He was happy to reduce his exposure, but still have some cash flow and diversify.