Actually the only key to be improve at osu is Practice a lot and challenge yourself. For CtB, only use dash when necessary or even in red fruit you have to control the catcher where he gonna teleport, also learn some usual pattern in ctb and know the mapper style. Spectactor's map your catcher gonna "swing" all over the time and it's full of red fruits, while JBHyperion's is in the other way, you have to be aware of non red fruits jump because you have to deal with a repetitive pattern or square in osu STD mode. Mazzerin's .... yah well just hold your dash until you fc that.
I have one clue if you use left shift button and keep annoy because sticky keys you can change that in Control Panel > Ease of Access > Ease of Access Center > Make the keyboard easier to use. Just turn uncheck the sticky keys. Also sometimes you can change the your key binding to improve your gameplay, also set your graphic in recommended setting.
So if you well enough to play ctb without mod, try one mod, I recommend you to play with Sudden Death mod first, and then the most common mod in CtB (Hard Diff++) is Hidden, and if you feel the song is too slow, use Double time mod. When you get well enough with Hidden or Double Time, try them both. And go try Hard Rock mod I know this one kinda hard because it elevate the Approach Rate, Overall Difficulty, Circle Size(Fruit Size) after that try to combine it with Hidden. The hardest mod in Ctb is Flashlight. Flashlight mode only playable in maximum Approach Rate=8.4 and after that only E.T or Alien can FC with that mod even with HR (True Story).
The last thing that I want to say is have your own skin or find a skin that you feel fit the most. Go stalk some pros in CtB some of them are generous, they share their own skin(Or their mix skin). If you really want to full combo a hard map (In CtB Difficulty) dim the background to 100% or if you just want to play for fun, just make sure the safest dim is in 30% (The lowest one). 0% Dim is not recommend because it very bright(even brighter with shadder) and can make your eyes hurt.
That's all I want to say, thank you for your atention
berhubung postnya sama jadi gw tulis ulang aja.