The things you need to do
1st get good on maps so you need a good map pool
2nd get some friends if youre a lonely scrub and use ts or skype for comms but remember to callout ingame since not every one is csi listening to you calls etc.
3rd get a better viewmodel now viewmodel is basically your gun and you can adjust it if its taking too lot of your screen
for the viewmodel generator go to workshop and search for crashz viewmodel generator
4th get a better crosshair
now you have to be carefull since your current crosshair might be good but your playing bad with it so acknowledge your prefences before making any adjustments!
For crosshair again go to the workshop in csgo hub and search for crashz crosshair generator
5th always warm up to get in shape. Now theres a lot of training/reflex maps but l'd go with dm or casual games just to give you some boost but in the end of the day its your choice
6th try to play with different screen configs aka like 4:3 stretch mode or 16:9 or etc now a lot of people including me likes to play stretch mode since its a bit easier to spot the game models but this will make your game look like a stretch tesco bag so l play with 1330x720
7th get a better movement for your reactions
You have to manually adjust your mouse sensitivity in order to get those kennyS no scopes (for tryhards onli xd)
In order to do this you have to manually go to your game setting and click on keyboard / mouse youll see your mouse sensitivity there and you can change it by your own taste
8th Wired or Wireless mouse? this still baffles a lot of people but l'd go with the same l am on right now aka the wired mouse since it wont give you any kind of lag while doing 180 or 360 degrees of rotations
9th always double check on your cords or cables of your microphone since a lot of people having this issue.
try to ask your teammates if your voice is laggy/weak since you can adjust your mic volume from your pc Start/Control panel/ hardware sound/ recording / volume. and you can listen yourself by talking and youll know if your mic is currently broken or not
l tried to put simple guides for the people having some issues with individual gameplay so l suggest you to go through every step and if you have extra time comment if this helped you :)
Have a good day and Enjoy your competitive gameplay xd (signed by dankboi35)