I've started buying my own fabric and getting my clothes stitched (shirts, pants, shorts, pyjamas). Yes, it's not nearly as convenient as picking clothes off a shelf, but the end result is more cost effective (despite not skimping on the quality of the fabric I buy), superior to what mainstream brands produce, and I also support multiple local businesses (the fabric store, tailors, the button vendor who sells me wood, coconut, bone, shell, and mother of pearl buttons etc.). It helps that I enjoy the process and that my partner is a designer and has a deep knowledge of all things related to the process. Goes without saying that you need an experienced tailor.
I still buy some things from the mall when I have to, but I'm trying to cut my reliance on 'fast fashion' as much as possible. Everything is geared towards convenience these days and it's wrecking our planet.