A bike can make noise when it is wet so sometimes after spraying with alcohol it will still squeak until it dries. I would first check proper alignment of the caliper and then make sure the brakes are bed in properly and then give us a report. Sometimes the squeezing method doesn't work. I tend to find a bit of both starting with a squeeze and visually aligning after and then alternate tightening of the bolts tends to work pretty darn well.