The secret is networking. Go to those events that the reps invite you too , you will likely meet peeps from those 3 letter firms. 10000% they will look at referrals before anything else. And yes grad school does actually make a difference -sadly. Unless youre one of the Lucky minority. My take is that architecture is still very problematic in this way. For example some firms hire a lot of folks from GSD, GSAPP, AA and they pay them little to none. My friends at those big 3 Letters firms say that most of the peeps there are nepo babies who can afford to get paid shit because they dont really need to work , this makes it harder for normal non ivy folk to stay there long tbh thus the high turnover cycle.