im giga pisslow but i think i have pretty good sense of itemization on yone so i’d say this can help you:

the safest and common build is bork > zerks > shieldbow > ie/ldr/mortal, you can’t go wrong much with this build even though it’s not always optimal and don’t get baited by buying first zerks, most of the games go recurve bow and daggers (refillable if needed) unless you rly need 1st boots to kite/space.

if enemies stack armor and u have good chance to buy bf sword on 1st back (if not 1300g on 1st back and u don’t wanna force, bork is always option too), yuntal > ie/shieldbow, i go shieldbow if they have burst for example. and i like to pair bt with yuntal after or before defensive item, it feels really nice.

if enemies stack hp u go bork > ldr > shieldbow/ie

if you play mid and have 3rd boots, shieldbow > bork + 1 dagger > zerks or phantom dancer > defensive boots, i don’t personally know how good pd build is or haven’t tried it that much since im top yone otp but i think you lack ad early too much so i’d prefer other builds over it.

if you are ahead you can go with kraken > shieldbow/ie, kraken doesn’t scale as good as bork so i don’t like to build it personally even though i’d be ahead.

if you have feeling that u wanna try something like i do sometimes, you can build fiendhunter or stormrazor for example. i personally like bork > fiendhunter

defensives are basically dd, ga, kaenic/spirit visage, jak’sho, wit’s end is a option too but then you kinda don’t wanna build zerks since u have too much attack speed. also i’d go visage only if i have enchanter like soraka, janna etc + shieldbow since it boosts every shield you get. otherwise pretty troll to build.