I know you prob don't wanna hear it but CFI is the best way to go as the previous posters stated.
But if you're totally against putting up the money for it networking is key and building hours the non-CFI route can be done. Getting a job fueling planes at a busy FBO or at a flight school will give you many contacts that might lead to a jump pilot, traffic watch, pipeline a small 135 outfit, etc. They used to be tough to come by but I'm not sure about now.