I'm new to jax and I mostly splitpush, can someone help me with items?

Can someone say a good build and which items I need to build 1st 2nd etc and also masteries/runes..And could someone link me to a streamer/youtuber that shows Jax combos/gives advice etc.Thanks a lot! The builds that I 've been trying are good like I 1v4'd twice and was able to solo carry a game but I just wanna try something new out, thanks a lot in advance!