I know it's way too early for fall posts, but I've acquired a few fall staples that I could not live without over the years and I have noticed that a few of them sell out very quickly. The items listed go on back-order fast (or sell out completely), so I suggest you order now. Although they may be pricey, all items last forever and are worth the price.
bean boots // I swear by my bean boots. Note these sell out fast and you need to order now. My go-to outfit for class in the fall is bean boots, Patagonia pullover, long sleeve tee, leggings, and camp socks. You can dress them up or down and wear them in snow or rain-- or just whenever like me. Also, note that L.L. Bean has a lifetime warranty. Here is a guide for purchasing bean boots and a video on how to style.
camp socks // If you get bean boots, you need camp socks. I get mine from L. L. Bean and J. Crew. Both are great, but L. L. Bean sells in packs of 2 and they end up being cheaper. I also wear these with my riding boots-- I have 10+ pairs at this point, but get so much wear out of them.
quilted vests // J. Crew makes the best quilted vests. I dress mine up and down, wearing them all the time on repeat. J. Crew and J. Crew Factory both make versions of these vests, and there is no quality difference. However, the J. Crew vests have gold buttons on the pockets- I have some of both and no preference over one or the other. I have the navy, khaki, and herringbone, which are all very versatile; they're years old and still going strong.