I start them as soon as possible, and put the where deer frequent. I try and put them where I want to have a stand, somewhat close to a bedding area for bucks. I use Monster Raxx,and have had great results pretty much wherever I decide to put it.
Any time now is good. I like to put them in a low spot that holds moisture most of the time. Where I'm from,we use a product called Rack Stacker (Canadian) Put this stuff on a rotten stump and watch it disappear.The stump method is great in dry years. I also use Deer Caine liquid on the ground.
Like now, I'm a stumper myself. Clear the area of debris, or around the stump if ya choose to do so. Then just bust up the soil a bit around it, pour it down throw a bottle of water on it for good measure and boom there ya go. I suggest Monster Raxx personally, it really actually works at attractin em along with some other wildlife in. Haven't got to see it add anythin to the herd yet but it's way to early for that yet
Get them started now. They need as much mineral supplement as they can get throughout the winter and if your looking for something to help promote antler growth and supplement the does with their milk and young'uns I would check out Monster Raxx. ALOT of "mineral" supplements are purely salt based which doesn't do a whole lot for either buck or doe. Clean out an area along a transition between bedding and food so you know deer use it frequent and they will find it. Its beneficial to find an area with easy access so that in summer and late fall your not disrupting bedding while freshening the sites. Its nice to get mature bucks to pattern to it and with it being in a transition are your setting yourself up for a reasonable kill during daylight hours.
Honestly you cannot go wrong with Monster Raxx. I believe they have instructions on their site. Tom is a great guy as well.
I try to put them in the highly travled areas...Around a stand location but not too close. Alot of guys on here would suggest monster raxx.... your own homemade blends...black magic...trophy rocks etc. As for when to start em...better question is when are they in need of nutrients and minerals? All YEAR long..it will not only keep your bucks healthy but your fawns and does. More nutrition when fawns are nursing as well. Good luck this year!!