Help with developing an NBA winning system

New to the forum, but not new to sports betting.  I generally bet every few days or so and only a play or two and don't look at too much past a few stats, streaks, and injuries, but I am looking to start betting on more games and am trying to learn how to develop a system.  Doesn't have to be perfect as I can tweek it over time, but I'm just in need of what I should include and how to go about building said system in a spreadsheet and how to collect the data quickly and efficiently.

Thank you to anyone who is willing to help, I know we all started somewhere back in the day, just today is my start.  

Thanks everyone and good luck throughout all your seasons.

I think that a good system right now is my "Lines(W-L)" system in cbb. Try it with NBA lines and see what you think. It can be done in almost any sport that has a line. I basically use it when I'm stuck between two teams/games. 

Good luck in your new system in whatever it may be.

im posting my plays from my model over in the nba section...

my advice is to focus on one sport (for me nba, although i do bet ncaab sat). From my years of betting i have never found a "system" but do have faith in numbers! i've created an nba model that uses personal rankings and key statistics (for example pace is very important in basketball). 

Once you can quanitfy your advantage you need to find a way of betting those advantages that works for YOU! everyone is different some people like the action some people would rather play one game a day.... at the end of the day (week) everyone wants to finish in the green!

Good luck !