Sunscreen application tips~

I used to just slather it on haphazardly, but it turns out there is a knack to applying sunscreen. First off, you need to apply it as the last step of your skincare routine, and apparently, applying it 30 minutes before going out is most effective. Also, it is important to make it a habit to apply it consistently, whether indoors or outdoors. Furthermore, I heard that you have to throw away products that are more than 6 months old... ㅠㅠ I really need to make sure to check the expiration dates!