I love the leather jacket because of the fact it can be worn with any outfit anytime. You can also find it in any store like H&M or D&G. I would wear the leather jacket with anything I have that is simple or needs a little bit of glamour or the "edgy" vibe. My favorite look of the leather jacket on me is the "dressy" look which is wearing a feather skirt for example it is black and navy I tuck in a sleeveless black shirt and wear the leather jacket over (afcourse not to forget a beautiful oversized clutch, some statement rings, and bracelets).
There also many looks than this look I described for you a lot of celebreties I have seen have worn it the casual way like with a ripped skinny jeans, a simple tank top, and combat boots. I am not a big fan of combat boots with leather jackets it looks too "rocker-ish" or "punk-ish" for me, but some celebs have worn it that way !
I have seen some celebs wear the leather jackets in a really cute chic way like Nicole Richie here.
I love how Nicole paired it up with a Maxi dress and wore a leather oversized bag to balance the look PLUS it is a very cute look for summer! You can also pair the leather jacket with a jumpsuit that is another trendy look for summer ! If you want to look rocker-ish or punk-ish you can wear it with a plain solid tank top and ripped skinny jeans with strappy heels.
Since it is still winter you can wear a leather jacket before it is an officially a trend in spring and summer. You can wear it over a dress shirt tucked into skinny jeans and maybe a faux fur vest over the leather jacket and ankle booties (The Jeffrey Campbell ones would look great !)
Overall, a leather jacket is an item where you can pair it up with anything, and you should wear it however you like. Anyways, I hope you had an idea of how to wear a leather jacket and liked what I suggested ! :)