First, pick an overcast wintry day with leaden skies.
Stumble back and forth with bagged bare-root trees, buckets, your planting shovel, some gallons of greywater, unless the county authorities are watching, in which case absolutely fresh well water will do, and a pile of twigs, a pair of side-cutting pliers, pruners, and about a six-foot section of recycled woven-wire poultry fence.
Set your distances by what you've got, based also on soil, slope, and region factors. Most of my trees are semi-dwarf, since they are not just for my generation, and I'm spacing them on a tight fifteen-by. You may want to go a little wider than than me, or try dwarfs instead, which will serve up fruit to you faster. My preference for semi-dwarfs is based on my probably mistaken observation that, once established, semi-dwarfs seem more drought resistant. And they live a little longer.
Dig a hole. Much bigger than the ones I dig (you almost certainly have a much better back). The one shown looks really tiny, but at least it's fourteen inches deep and seven across, measured. You want your roots unscrunched and pointing downward, and your finished unmulched ground level to be right about where the tree was grafted. If the tree is a full dwarf, maybe a little shallower, so that the grafted fruit tree doesn't form its own roots, resulting in a full-size standard. Eek!
Shown is a four-foot Lambert Cherry. There are other cherries on the premises, which are advertised to pollinate Lambert, or each other, so that there are cross-pollinated early varieties and cross-pollinated late varieties. There are many good books to help you work this out for each kind of fruit tree. The rules are different for some from others. You may also want to talk to your extension agents, or if they have all been fired, your Master Gardeners, who work for free.
Untwist the loops on the ends of the wire "twistie" that holds the wet-sawdust-enclosed "bare" roots in a plastic bag. Slip the bag off the roots, letting the sawdust fall into a plastic bucket, maybe, or on the ground, as suits you. Drop a little dirt around the deepest roots, then pour in your ... water ... then add more dirt, jiggling the tree very gently as you go, to get the soil up against all the roots with no air pockets. Keep this up until you have level ground.
Our soil and our trees like each other a lot so I haven't bothered, but in some places or with some trees, a reason you will want that bigger hole is because you want to put some well-rotted compost in the bottom, beneath the first dirt upon which the deepest roots come to rest.
Now cover the dirt around the tree with a mulch of the sawdust or wood shavings that came with the tree. Flatten gently, pushing away any chickens that come around to scratch it all up. Push them away again. And again. Lose it, and chase the chickens around with the shovel, while the people waiting their turn at the stop sign across the intersection sit in their car open-mouthed at your abusive, unhinged behavior. You should have moved farther out into the country -- too late now, neh?
Catch your breath, get out your pruners and reduce your pile of twigs and such to a pile of shorter twigs and such, and place this ugly mess all around your lovely tree on top of your lovely sawdust or wood shavings, like a very dead wreath. The pretty mulch will hold moisture and feed your tree over time. The ugly stick mulch will help shade the pretty mulch and the base of the tree, holding the moisture even better and also feeding your tree over time.
Now take your side-cutting pliers and build your anti-chicken-scratching device, a wire cage for your tree. Since this is salvaged from fencing that a prior owner of your place pulled with a tractor and then ran over, you've had to work hard to get this six-foot length of it cut and straightened out, but now have sufficiently little regard for its appearance that you don't mind snipping a few lengths of wire from it, shaping "tent-pegs" from them, and pushing them into the ground around the corners of your tree cage so the chickens won't swarm under it to commit their *&%$%$ mayhem on your mulch.
The books go on and on about how to stake your tree so it won't whip itself around in its hole and make a cone-shaped tree-drying tunnel, but I've always found the wire cages seem to do the trick.
So why is your orchard in the chicken pasture?
Birds like shade. Grass likes a bit of shade through some part of the day, at least around here it does, because our summers are almost all droughty, and the shade retains ground moisture along its sweep across the grass throughout the day -- which is also good for the next tree over. And the poultry love dropped fruit. They will clean it all up and leave you the harder-to-reach ladder fruit, without having to have any of it brought to them. Win-win.
Now go take a long nap.