You can make "Gatorade" out of just about anything.
For "natural", start with a fruit juice you like. You want to dilute it down to about 100 calories in 20 oz. Now mix in "Lite Salt". This is a mixture of Sodium Chloride and Potassium Chloride. I use 1/4-1/3 tsp per 20 oz. You may need less, depending on how much electrolytes you sweat.
I use regular kool-Aid. (Yes, I am a kool-aid drinker
)
I don't like how sweet regular sucrose makes the drink. I use a mixture of dextrose and sucrose. For 64 oz here is my mix:
1 tsp lite salt
1 package of kool-aid
64 oz water
3/4 cup dextrose
1/4 cup sucrose
if you like it sweeter, adjust the ratio to more sucrose. Less sweet, more dextrose.
Dextrose is found at home brew stores or at Amazon.