I got better by hardscoping then once I got comfortable with that, I started quickscoping.
Once you learn to quickscope you will get better and go like 49-15 or something like that in a sniper only match.
You can find for some videos on YouTube teaching for you, already has been posted here too.
quick scope
but you can trying it with your friends first
..
1st Get used to Hardscoping 2nd get used to no scoping and 3rd QuickSCope
really really good tutorial
Just quickscope but remember to put knife with ur sniper .
Quickscope that was you are gonna be !
Go to the tut section somebody posted a tut bout sniping.