Hey Shaun:
Personally I use a table vice, a big one so it is heavy enough that it doesn't 
need to be bolted to the bench, but you can use any type of vice that will be 
fairly stable and won't move easily while your working.
Typically, for a mike plug, I would put the end opposite of where you are 
soldering into the vice, using some sort of padding if it is a metal vice to 
prevent any damage to the plug, and have the pins that you want to work on 
sticking out just enough to work on them.
Some mike plug pins will have a small hole in the pin that you can run the end 
of the stripped wire through and fold back to keep it there while you solder.  
Most don't though, and your typical mike jack pin is sort of a U shape where 
the wire is soldered into the valley of the U.  Steve's suggestion to tin the 
end of the stripped wire is a good one if you know how to tin a wire.  
Basically it is melting solder to the end of the wire to both keep it from 
fraying if it is a multi-stranded wire, and so that when you put it against the 
contact you wish to solder to, all you have to do is touch the soldering 
iron/pen to the wire while it is against the contact and it'll sort of solder 
itself on.
Otherwise, you have to try and position the wire, hold it, hold the peace of 
solder in the right place and then touch all four things together, that is, 
wire, contact, solder and soldering pen.
I would recommend to work on tinning wire for a while, and once you get it so 
that the wire has a nice clean coating of solder on the surface, start 
soldering your mike wires.
All this said, it gets extremely tricky soldering 8pin mike jacks because the 
pins are so bloody close together.  This can be slightly over come by using a 
very fine tipped soldering pen/iron and very small gage solder and keeping your 
consentration high while your working.
For most projects, a relatively light gage of solder is best with a 25 watt  
medium tipped pen.  The terms pen and iron are interchangeable mostly.  You can 
also get solder guns which are shaped, oddly enough, like a gun.  Most 
soldering irons come with a couple tips, one fine and one medium fine.
That just means the actual tip is smaller and sharper when its a fine tip.

As for soldering without burning your fingers, well, you need to have very good 
spacial sence to solder as a blind person.  You have to be able to gage the 
distance from the end of the soldering iron to your other reference finger.  
You can use the heat of the iron to get a good idea of how close it is.  
However, burns seem to be a fact of life when soldering in close quarters.  
This is why it is good to use a vice or large device to hold your work because 
then you can always have a good hard tactile object to refer to.
vice grips, plyers, heavy objects to keep the plug in one place will work.
the rest is really up to your own bravery and personal learning methods.
73
Colin, V A6BKX