A good tip for hot summer days is walking with your water. During the hot summer days, we sweat more often and as a result, our bodies tend to need more hydration. To combat dehydration, I walk with my water bottles everywhere I go. For instance, this weekend (sunny weather), my boyfriend had a cricket match; and if you know anything about cricket, it lasts hours (5+ hrs).
I fill it up first thing in the morning or when I plan to go outdoors. This way, I always have water to drink & I don't have to spend money on those pesky, water bottles (which can add up). I recommend reusable bottles like the one pictured below.
I hope this tip keeps you hydrated during the hot & humid summer days.