Summer is the perfect time to connect with nature, soak up some sunshine (don't forget your sunscreen), and enjoy the great outdoors. Plan a picnic with your favorite foods, go for a relaxing walk in the park, or, if you're a fan of the night sky, spend an evening stargazing. You could also join a hiking club or try outdoor yoga. These activities not only provide a healthy dose of Vitamin D but also help reduce stress and increase happiness.