Beach days taught me that one morning application is not enough. I used to put on SPF balm once, then forget about it for hours, especially if I was swimming or drinking something cold. Since I wanted a product I would actually remember to reuse,
https://bitchstix.com/product-category/spf-balms/ became the kind of page I checked for SPF balms that were easy to keep in a pocket or bag. Now I reapply before long walks, after eating, and after being in the water. I do not make it complicated. I just treat it like normal sunscreen, but for lips, and that habit helped a lot in summer.