I'm guessing all this was said before somewhere, but I highly recommend doing different modes of this for at least 15-30 minutes a day, its fun anyway imo:
http://steamcommunity.com/sharedfile.../?id=213240871
change the shots to kill to 3-5 and practice movement with counterstrafe-stop bursts, or set size to heads and practice oneclicking AK/USP with movement/stop. Will speed up and sharpen your muscle memory development.
Also, buy a steelseries QCK+ or other similar large mousepad. Its 15 bucks, panhandle it if you need to. "Fast" sensitivity in this game is 30cm mouse moved per 360, something standard is ~45. Some people play at 90+ but they are not the norm. cm/360 is the best gauge as diff sensitivities produce diff results depending on mouse DPI, m_yaw, etc. Regardless, my point is a large mousepad is a huge upgrade as you need the space to be able to scan correctly with a sensitivity that doesn't F you for everything else (the surface seems perfect/fast too). I'm pretty sure the mousepad was the biggest upgrade for me from what I had vs zowie FK mouse/144hz monitor/steelseries cherry red switches keyboard, although I love them all