Hi AkRowidy09, welcome to our forum.
Here you can find a topic about debadging:
debadged-rogue-t370457.html?hilit=debadge
This forum has a beautiful "Factory Service Manual" link. You can access it from here:
http://www.nicoclub.com/FSM/Rogue/
The Front Nissan emblem is easy to take off. Just couple of plastic clips are holding it.
Go to
http://www.nicoclub.com/FSM/Rogue/2011/EXT.pdf
Look at Page EXT-19 for the front emblem removing
The rear one is attached by a double sided foam tape. If you remove it, you need to replace the tape to install it back.
An advice: You can use a special spray paint called "plastidip". The good thing about this spray is after it dries, you can peel it of if you dont like. Here is another forum member with Plastidip applications:
blacking-out-whole-car-t403338-30.html?hilit=plastidip
Good luck!