I made my choice. I decided to get Battlefield on PC instead of PS4. So with that I was wondering if you guys have any tips for someone who hasn't used a m&k to play games in a while. I know I'll get killed but any help would be nice.

There is nothing to it other than to not give up after constantly dying. The community in BF3 did a decent job of having servers being labelled as "noobs only" which most people abided by. You're still going to get some level capped players going into those servers though just to fuck with new players.

You point at things with the mouse, just like you do when clicking things on a PC otherwise, I'ts pretty intuitive. And if you do find it hard, it should get better fast with a little practice. Also, if you are good at console shooters, then most of the important traits that separate good players from bad ones should carry over. I doubt an experienced player would lose badly against new players even with a control handicap.

Practice and become familiar with key binds. Tweak whatever isn't working for you until you feel comfortable. You might also want to disable mouse acceleration before you start practicing or it "might" have an effect on you later down the road. I noticed after playing with it on for so long you get in a bad groove of over compensating in other games because it became ingrained in me. You might not notice it in Battlefield but it's very prevalent in Counter Strike. I would do it just for the precision you will gain.