As a relative newbie to sports investing, I thought I'd share my bad wager of the night because I've seen a few other new people arrive recently too.
Maybe it's just my inexperience, but I was so sure Bucks would win at home tonight that I put a maximum of 5 units (5% of my bankroll) on the ML for Milwaukee to win, just to pick up a little extra "sure cash". Of course, Philly just finished winning by 15(!) a few minutes ago. So, it was obviously a doomed wager with probably no value at all, but my point is the 5% rule protected me here. My bankroll is still up over 60% in just a few weeks, and tomorrow is another day.
I just urge the newcomers especially to read and reread anything you can about money management from the people who have been doing this a lot longer and know a lot more. If you're risking more than 5% of your bankroll on any one event, I am believing the folks who say that this will get very ugly for you at some point, unless you are made of unlimited money. Anything can happen.