You may be a good candidate for one of the robo advisor services (wealthfront, betterment) or if you occasionally need a person try out vanguard personal advisory service. The fees are relatively low and gets your excess cash into the market.

I think most of your friends on here and the bogleheads reddit , which are both full of great information would recommend you do it yourself, but I figure if you were predisposed to reading up on modern portfolio theory you woulc have done it already.