。
She tried to fasten the earrings to her ears.
Literal
She [topic-は] ears [on-に] earrings [object-を] fasten-let's [quotative-と] did.
イヤリング is borrowed from English 'earring' but in Japanese typically refers specifically to clip-on or screw-on (non-pierced) earrings — pierced ones are usually called ピアス (from 'pierce'). This sentence's 固定する ('to fix in place, to fasten') and the slight struggle implied by ~ようとした are consistent with the イヤリング reading: clip-ons can be fiddly to position. 固定 contains 固 ('hard, firm') and 定 ('settle, fix') — both contributing to the 'lock in place' sense.