The context here is approaching whilst in college (on campus) so i'm invested in preventing too much negative social proof from harsh rejection. Do you recommend looking for signs of attraction before approaching to boost my chances of success in this context?

I was reading Bonecrker's material and he suggests looking girls in the eye and observing how their body language responds in order to determine the small fraction of girls that will be receptive to approach. Do you believe this would is a valid move?