I have procured a Raspberry Pi Model 3 few days ago and planning to (safely!) overclock it. I want to get maximum from my little Pi 3 and looking for the instructions for the safe overclocking. I am also planning to install heat sink on the pi. I tried searching internet and stackoverflow for the detailed instructions. However, I could not find satisfactory step-by-step guide for safe overclocking of Pi3.
https://www.raspberrypi.org/forums/viewtopic.php?f=66&t=138123
https://www.raspberrypi.org/forums/viewtopic.php?f=29&t=138840
http://www.jackenhack.com/raspberry-pi-3-overclocking/
http://hackaday.com/2016/03/03/overclocking-the-raspberry-pi-3-for-tasty-speed-increases/
https://github.com/retropie/retropie-setup/wiki/Overclocking