While taking your laptop and blowing some of the dust out of it might make a bit of a difference, you'll really need some cotton buds and some alcohol to do a good job. I used to do the blowing the dust out thing on my old laptop until I realised that some of the dust was actually caked onto the fan blades and there was a significant improvement in airflow once I'd cleaned each of the blades individually. You just need to be patient and careful with the alcohol.
Asus ROG G751JT-T7115H
17.3" IPS, Intel i7-4720HQ, 16Gb RAM, NVidia GeForce GTX970m, 256Gb M.2 SSD + 1Tb SSHD