Just in case the winter frost has fogged your memory of proper things to pack before heading out onto the course in the heat this should help. First and foremost water is vital to your survival on the course. Drink plenty of water before you get on and off the course and pack at least one water bottle in your bag. That’s the bare minimum but if your feeling like you need a bit more add a few more water bottles, some ice, and Gatorade or something to help give you back electrolytes.
If your just hitting the course after being confined to indoor spaces for the winter it’s a good idea to apply some sunscreen. Even if you’re not just reentering the outdoors after hibernation it’s still a good idea to lather up, not too much though your pores would still like to breathe.
As far as clothing goes if cotton is all you have to work with you will be fine. Try and stay away from heavy sun catching colors like black. Lightweight clothing is the obviously your best option so you’re not lugging around a heaving shirt and heavy golf bag. However, if you would like to be a little more comfortable use a moisture wicking shirt like Dri-Fit or Under Armour. Adding a hat to your golfing attire is a good way to keep the sun out of your face and let you see the course without too much distraction.
Bringing along an extra towel is also a good idea. Switching between a few different golf gloves or at least taking the glove off between shots is a good way to keep the longevity of your glove and cool off your hand.
With all that off your checklist you should be ready for a great round of golf.