I'm not one of the old pros here, (just old), but I do have several generations of SF under my belt so ill help ya ifn I can.
I collect in pint jars, write the number jar, % abv, and proof on each one. As I collect, I cover with a coffee filter and screw the ring down around the filter to keep bugs and dust out. Now, I think its very important to let them air out 2-3 days before making any cuts. The lighter alcs will be lost to the angels and you'll loose some abv, but were not about just making rocket fuel now are we??? Temperature seams to effect the airing, seems like the warmer it is the closer to 2 days it gets. Tha cooler your collection jars are, might take 3-4 days before you can make the distinctions between em.
Now, when it comes to making cuts, I like to have some Salteen crackers and a glass of ice water handy. Start in tha middle, work towards both ends. Put abouta 50/50 water to sample in a spoon, smell it, taste it, does it burn under yer tongue? Leave it out. Then spit it out, thers plenty of time fer drinking later...chew a cracker, rinse with water. Repeat, workin both ways from the middle. Some times Ill grab one of the head jars on purpose to remind my tongue/nose what I don't want. I do like going into the tails further than the heads, hell, that's where the flavor is... but ya gotta be kinda careful. You can overdo it. Remember, you can always add more flavor, its a b°π|√πch to get out. After you've determined the jars ya wanna keep, add em up, figure yer average abv, figure the % you want to dilute to, then figure how much water it'll take to make it happen. PUT THE WATER IN THE MIXING VESSEL FIRST, I use filtered water (Berkey). Then add the jars slowly. Make sure they are about the same temp as yer water er else your product can become cloudy.
As for your tails, mine become cloudy, but I keep running em down to about 20% or till I'm just too wore out to go any further. Keep yer heads and tails fer a good ol slow spirit run, good stuff, but remember to dilute down below 40% before stillin. Ya don't hafta worry bout filtered water at the same temp or water first fer yer spirit run dilution. Just that its down below 40% for safety.
In the end, heads and tails are up to you. Heads have headaches in em and in most everything you buy
"They who can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety." Benjamin Franklin