I washed it thoroughly with soap and warm water before I used it the first time. Over the past six months before I use it I just run it under warm to hot water for about 10 seconds and rub it a bit before and after using it, kinda like a mouthguard
The important only is keep it clean when's out of use. Dirty paci left in some humidity place can destroy latex, in combination with high temperatures the corrosive process going very fast. Silicone teats are more resitent.