I’ve worked farm work in humid heat before, with long sleeves plus armor to protect against knives.

My main advice is this:

• Get a big container you can fill with water and ice. Find a way to keep water close to you so that you actually drink it. Avoid if possible a scenario where you need to walk a long distance or ask permission or cross obstacles to take a drink.
• Buy salt tablets for hydration. You can find them on amazon. Ask anyone who works construction for their advice on brands I don’t remember what exists
• Meditate a little bit each day to develop body awareness. Learn to detect internally when your body’s in distress.
• Make an ongoing study of this. Don’t just adopt strategies then keep them forever. Make it a point to do a little more research each month into: physiology of hydration, medical signs of heat problems, how other companies are handling heat, etc