Other writers have described proper conduct and proceedure once a melee is underway. What fighters should do, who healers should heal, don't stand too close to fighters who need to back up, etc. I shall talk about the journey from Puddleby (or other gathering point) to the scene where all the action takes place. An Expedition has several phases:
Reasons for an expedition include:
It is the Leader's responsibity to ensure that the right people are present before the Expedition leaves. The Leader should be well aware of the danger level of the target area, and ensure that the fighters and healers are adequate for the location. (No sense taking new exiles on a Rescue in the Desert, after all. They'll just end up part of the problem.)
The Leader can use a sunstone or general \yell-ing in Puddleby to gather fighters and healers.
Either move to one side of the gate, or temporarily take over one of the many buildings in Puddleby.
The next step is for the fighters to share with the healers. This is very important. To the healers, at least. You are encouraging them to leave the relative safety of the town, and go out and die. Share. If you can't share, because there are more than 5 healers in the party, then \give. Sharing is important, because it allows the healers to identify party members once you get out into the dangerous world.
Likewise, healers should share with the fighters. Not because they will kill anything, but to let the fighters know who to protect. This is especially important if the healer is not wearing white clothes.
Note that two healers are usually better than one, because they can heal each other. A party who's sole healer dies is SOL and forced to stop until another healer wanders by.
A decision to make now is whether the party will stop along the way to heal bodies, or whether they will blow right through and pass along a message. Stopping might gain your party more bodies, but time might be of the essence. If the party does not stop, one healer should be ready with an apology as they zoom through.
Most healers are constitutionally unable to let anyone be in less than perfect health, and feel real pain upon seeing a fallen exile. Nothing discombobulates a party more than half the healers stopping to raise a body while the rest blasts along.
Once you get away from Puddleby, most exiles will be well able to decide whether they are strong enough to join your expedition.
One party member should be designated the Navigator. (This may be the Leader, if he is the only one who knows where to go.) Their job is to \yell the direction the party should be travelling. This will enable stragglers to catch up.
The Leader has the very important job of deciding when to call halts for a regroup. And the even more important job of deciding when the area is too dangerous, and calling for a retreat.
Place your strongest fighters in front. They should have the ability to roll over lesser monsters without stopping. They clear a path for the body of the party.
Have the 1/4 weakest fighters bring up the rear, after the healers. Have the mid-level fighters on either flank. Their job is to intercept any wandering monsters and hold them away from healers until one of the strong fighters turns back and nails it.
Modify the above percentages based on the terrain. For example, in the desert, with very fast, very deadly-to-healer monsters, the strong fighters should be spread equally around the party.
Full speed means that stragglers cannot catch up. Full speed means that healers cannot heal "on the run". If a wounded fighter moves at half speed [ooc: put the mouse halfway to the edge] and a healer runs right behind them, they will bump back and forth, and the fighter will be healed. For a healer who has trained with Fastus, you can do a considerable amount of healing while covering respectable ground.
Some areas are too dangerous to move at anything less than full-out. (Again, the desert and snowy place come to mind :-) The Leader is responsible for declaring this via a command like "Run". After a "Run", time must be spent to call for stragglers.
First, reward your healers again. Verbal thanks is always nice, but a \give is always welcome -- especially if you've killed some really boss monsters and garnered up some real money.
Typically, your party will split. Some will want to go continue adventuring in this area. Others will want to go back to Puddleby.
The last job of the Leader is to arrange an escort back for any healers who want to go home. This is usually less arduous than getting there, because the countryside is less wild near Puddleby. A large group of fighters can escort healers out of the "danger zone", or to a mirror, without going too far out of their way.
I can personally vouch for Lord Dodge as a good Leader.