Avoid fluoridated water, which can be difficult if you have city water treated with it. A simple suggestion is to follow nature-, be physically active during the day, go to sleep when it's dark. Sleep without artificial light (television especially). Depending on how seriously you would like to take it you can also make sure to get all of the minerals most of our diets lack such as zinc, iodine, etc. additionally the best thing to do is exercise the gland through meditation as well as even just creative activities.
I do hope you do your own research on the subject. Research your pineal / third eye and see what it means to you. Peace