I got this from a qdm site many years ago and have had good luck with it. The only other thing I add is Lucky Buck. They seem to eat it faster when I mix the Lucky Buck with it.
You can make your own mineral mix for a fraction of the cost of store bought ‘mixes’. There doesn’t appear to be any scientific proof showing minerals will improve the health of your herd. But at the very least a mineral site is an excellent location to place a trail camera and get a survey of who’s in town. Deer will typically use mineral sites beginning in mid to late winter, and continue to frequent them until late summer.
Ingredients: Makes 250 lbs
Di-calcium phosphate – 50 lbs
Trace mineral salt – 100 lbs
Stock salt – 100 lbs
Di-calcium phosphate is a dairy feed additive bought at feed stores.
Trace mineral salt is red and loose kind without the medications. Look for the highest amounts of calcium and phosphorus on the label.
Directions:
-Mix all together well but not until ready 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.
Optional method:
Use an old stump and pour the mineral mixture over it. You may want to cut the stump with a chainsaw to create some additional openings for the mixture to catch in. As the stump ages and starts to break down, the minerals will be absorbed into the wood. Deer will literally eat the wood to get the minerals out of it.
Feel free to experiment with the ingredients. Add a bag of dry molasses, use trace mineral salt with selenium, etc. They all work
I placed about 30 lbs in each site location. Thanks Bob for the recipe! 
