Hi Whistle
Lay the chains spike down, neatly and evenly behind the tire, tie a short piece of rope to one side end chain link, then tie the other end of the rope to the side chain end link on the other side, leaving a foot or so slack.
then pull the rope big loop over one of the lugs on the tire, drive the tractor slowly forward, trying to lay the chain out evenly on inner and outer. This will pull the chain up and over as you drive. Don't worry about the inner diamond cross link chains yet.
keep driving forward until the chain is all the way under the tire and even out a foot or so out back. By this time the free end should be up on the tire a foot or so.
then untie the rope and attach the inner, then the outer side chains, relatively tightly, then it's time to do the diamond cross chains. Because the chains are sold to fit various tire sizes you will probably find that you will need to cut off some links to make for a nice neat job. Those cross links are heat treated and very hard...a hack saw will take all day...I used a carborundum cutoff disc. Careful you don't cut into the tire, or mark them with chauk and take the chains off and cut them in a vice. The point is do it right once and every year you put them on it'll get easier.
My chains came with a kind of twisted dogbone(for lack of a better term) connector but I found these worked their way unhooked and off, so I replaced them with some screw links I bought at the hardware store. They work fine. Coat all threads with neverseize.
Hope this helps
simonmeridew