Learn when and when not to CSGO Skins liquefy - If you've got a good number of bullets left on your magazine and think an enemy is close, don't start reloading and get caught with your trousers down. Reloading takes some time, and you need to just do it when you feel you're safe from enemy fire. If you run out of bullets in a firefight, switching to your pistol is going to be much quicker than attempting to reload mid-fight.
Learn to be patient on CT side - Something you will see again and again in low-rank games is impatient counter-terrorists. When playing the CT side (assuming you are playing a defusal map, which is the predominant competitive game style), your job is to hold down the bomb sites rather than let the terrorists plant the bomb. If you're pushing past the bomb sites and searching around for terrorists, a smart terrorist group will simply wait out you and kill you when you push. Do not do it. And find out how to punish people to do it when you are on terrorist side.
Pay attention to your role in the team - Team essay is important. Make sure you're searching around and seeing what your staff is up to before you buy a gun. If a person comes with an AWP previously, you generally don't require a second one (there are exceptions to this, which you will learn, but play it safe). If a teammate doesn't have any cash and you have enough for numerous firearms, buy two and drop one for these. As stated previously, if your group is broke, do not buy from sync together - wait for them to save for a round and then buy together. It is a team sport, play so.
Do not anger! - This one's probably obvious to lots of people, but CS can be a difficult and frustrating match when you're losing. And if you can not do that, at least do not broadcast your frustration on voice CSGO Items comms. Nobody wants to hear the way bullshit their teammate thinks this game is at the center of a round.