You see I have nothing to offer anyone outside of the gym. I'm not that successful, my Milan isn't a very flashy car, and I have a terrible personality. The only thing I have going for me is my gains. Flexing and lifting heavy objects outside of the gym is generally frowned upon. If you flex at a bar you look like a douchebag plain and simple. If you are too eager to show your strength you look like a tryhard; a tryhard is actually taxonomically related to a douchebag. Douchebag is the Family and tryhard is a Species within that family.
The gym is the only place where you can flex and lift heavy ass things. But there are degrees. You can't just waltz into the swolenasium and start flexing in front of the mirror and lifting shit all willy-nilly. That would make you look like a douchebag too. What happens if you get stuck under something that weighed too much. What gets chicks moist in the gym isn't the dude who wants to be noticed - it's the dude who doesn't care if he's noticed.
Check this out. Let's say you walk into the gym and you load up the hack squat with a million plates. You hop into the hack squat and instead of squatting you start shrugging your shoulders and grunting like a gorilla. Then after shrugging what you think is a herculean amount of weight you hop off the hack squat machine and start sulking like you're a god damned Sith or some shit.
Well no one is going to think you look cool. You look like a fucking dickhead (another species that is taxonomically related to douchebag). You might have more weight on the hack squat than God can comprehend but any chick with a brain in her skull is going to know that what you're doing seems wrong and looks insanely stupid. Hell she might even walk over and put on more weight and start shrugging that shit too. That'd be embarrassing. Serves you right though.
So what's a bro to do? Be smart, use proper form, and use the god damned hack squat like it's supposed to be used. You need to be smart about what you do to get her attention. You can't just see her mid-set and dart over to a more glamourous workout. That is if you see a beautiful cardio bunny gazing your way and you're in the middle of calf raises it isn't smart to stop doing calf raises, grab a bunch of dumbbells and do curls. She's going to know somethings up.
It also doesn't help to have shitty form. A guy doing shit reps or not doing squats properly is going to look ridiculous. He's not making natural movements. Everything you do in the gym should make biomechanical sense. You look incapable or wounded if you don't have perfect form. So work on form so that when there is a honey at the gym you can bust out a perfect set, get some gains, and maybe make her stir a little bit.
Whatever you do don't drop the weights or grunt to grab her attention. I drop the weights when I'm playing with the deadlift, but that's what it's meant to do. I'm not trying to make a lot of noise, I'm just doing shit they way it's supposed to be done. Same deal with grunting. I'm not grunting to draw attention. I might let a little grunt out when I'm pulling 425 for deadlift. But if you grunt all the time or scream "FUCK" after each set she's going to think you have the maturity of a child or some deep-seated personal issues. No chick wants to bang a dude with anger issues or a dude with the maturity of an attention seeking 12 year old. She might be willing to bang a dude who is physically capable of lifting something kind of heavy and not being dramatic about it.
This is how I choose to hit on babes at the gym. Sometimes I just want to run up to them and start curling things and ask them if they'd ever seen rotator cuffs as big as mine, or if she wants me to show her my thrusters. Unfortunately I know how that would end up. I'd end up with a slap to the face, I'd lose my gym membership and I'd have to start doing bodyweight exercises like one of those uppity ass marathoners.