[Need Help] How do I improve my aim?

Hey folks, I'm new to the PS4 and console gaming in general as I used to be a PC main. On PC my aim is decent and I'm well capable of playing fast paced shooters without any issues, however on console I can't get used to aiming with analog sticks as of yet. How did you improve your aim? What's your controller layout? I'm looking forward to playing CoD WWII and BF4. And no, I did not switch entirely, I just bought the PS4 as an addition to be able to play with my girlfriend and a couple of my friends. Thanks in advance for your support! Kind regards, a console newbie