To prevent wooden utensils from splintering, regularly oil them with food-grade mineral oil or beeswax to maintain moisture and prevent drying out. Avoid soaking wooden utensils in water or exposing them to extreme temperature changes, as this can cause the wood to expand and contract, leading to splintering. Additionally, handwashing wooden utensils and drying them thoroughly after each use will help prolong their lifespan and prevent damage.