Here in Oklahoma some folks would rather eat the squirrels over deer. I just think of them as rats.
Wheat Bran deer mix
the following copy and pasted for a mineral mix.
No secret.
WHITETAIL DEER HOMEMADE MINERAL MIX RECIPE 
Ingredients: Makes 200 lbs. for about $23.00 
1 part Di-calcium phosphate, this is a dairy feed additive bought at feed stores. 
Comes in 50lb Bags at around $11.00 you need one bag. 
2 parts Trace mineral salt, the red and loose kind without the medications. 
Comes in 50lb Bags at around $5.00 you need two bags. 
1 part Stock salt, ice cream salt. 
Comes in 50lb Bags at around $2.00 you need one bag. 
Directions: 
-Use a 3 pound or similar size coffee can to use as your measure for each part of the mix. 
-Mix all together well but not until read to use, keep ingredients separate until ready to put to use. 
-Dig or tear up a circle in the soil about 36 inches wide and about 6 inches deep. 
-Mix your mineral mixture with the soil. 
Maintenance: 
-Replenish in 6 months with fresh supply of mineral, and then each year there after. 
Helpful hints: The best time to put it out is March/April and I put all 200 lbs in one hole. Also I like a water source to be within 100 yards.