Before attempting this task please ensure the power to the oven has been switched off .Fat and food deposits may build up around the lamp cover and can sometimes seize it in place. This will make it difficult to unscrew. For extra grip wear a marigold glove, grasp the cover with the gloved hand and turn anti clockwise to remove it. Now turn the bulb anti clockwise and remove it. Fit the new lamp bulb and cover. Be careful at all times when you are handling glass items.