[misc] How can I find out which ingredients my skin is sensitive to?

Hi guys! I've come a long way in my skincare journey since joining this sub a year ago and made a lot of progress. It's been a roller coaster of a battle though against my acne due to the fact that my skin can be pretty sensitive and reactive against certain products.

I was wondering how others here are able to pinpoint which ingredients their skin is sensitive to? At this point I know that I can't use any products containing salicylic acid. I know that because I've used several different products and brands and applied them in different order and had terrible reactions to all of them. Same with coconut. If it's in any cosmetics or skincare I get clogged pores and breakout.

Other than those ingredients I'm not sure what I'm sensitive to. I have a list of products that my skin has had reactions to and I have a list of products that work perfectly well with my skin. How can I figure out which ingredients I'm sensitive to so I don't have to keep guessing if a product will work for me before buying it?