Want one? Try Etsy (look for letter jackets!) or there are some good repro options available like this one from Zara. They key is to get an oversized fit - like your hot boyfriend who plays varsity baseball gave you his to wear around school so everyone knows you're his girl.
Here I paired it with another awesome vintage find (a linen jumpsuit from madewell, scored during the same succesful thrifting trip!)
To complete the look I did absolutely nothing to my hair. I washed it three times with my mom's Viviscal Shampoo, then used the Ouai Treatment Mask, which I left on for a 45 minute bath. When I got out I brushed it with my mom's Tangle Teaser. I did sit in a nice steamy kitchen for a while waiting for my stepdad to make corn on the cob, so that may have helped. Then I went to bed. I do not understand this alchemical magic that has suddenly made my waves look how I actually want them to, but I am complaining and I really like it.
Anyways, I think I captured the look, which is like "Ya, I may be 33 but I am just as cool/cooler than I was in high school." Or I am wearing this ironically, because I was a total nerd in highschool but now I am hella ironic and hip. Hard to tell! And that's half the fun (I am neither, I just loved the Breakfast Club, and the music video for Colors by Halsey)