Make sure the vent screw is done up tightly (you don’t want your board taking on water and sinking).
When your board is not in use, make sure the vent screw is loose or out so the surfboard can breath. Never leave the board in the heat with the vent plug done up. The air inside will heat up, expand and pull the board apart from the inside out. Don’t leave your board in direct sun light for long periods, especially in a hot car.
If your board is bagged up for a long period, completely remove vent plug and make sure the airway does not get blocked.