BenJLiu :
Tolis_GR :
BenJLiu :
Tolis_GR :
What pc case do you have?
CoolerMaster Masterbox 5 White
Nice case. So, there is nothing difficult to this. Simply align you fans to the fan slots and use the screws to tighten them to your case. As i see you can install 3 at the front and one at the back. What exactly is your problem you are facing? You can not find the fan slots? This figure from Coolermaster's site may help you.
http://www.coolermaster.com/case/mid-tower/masterbox-5-white/
The thing i find difficult is that when i screw the included screws, the screws wont go down into the hole of the fans. Also, as i screw the screws deeper into the fan, the screws seem to be resisting when i screwed less than half of the screw in.
This is normal. As you addressed, these are self tapping screws. Which means that when you screw them, they create a spiral to the plastic. Just go on until the screw positions the fan firmly to the case. Important is that you have to screw little by little with cycles. ie screw by half the first one, then the second, third and so on. Do it by cycles until the fan is firmly in place.
P.S.: Do not overdo it with screwing or you will damage the new spiral you just made and the plastic