First install the free Texporter plugin which
allows to send the meshes's UVMapping on an image.
Second is to add a UVWMap modifier(select planar),
then separate in groups of your choice(preferably small amounts of faces for each one),
after you separated all groups(an invisible object frame/matrix still exists when you separate all faces from an object,delete it by getting out of the sub-objects operations and simply hit delete key)
Choose a group to start with(usually I start with the head or torso) and add an UVWUnwrap modifier to it...From now on there are many different ways to texture but the easiest is to hit the Sub-Object button and select all the faces from the current group,click on the edit button to see the Uvs and go back to the Panel to hit the Averaged Normals button...now this will place the UVmapping according to the shared-angles of your groups so if there wasn't any more difference than 45 degress between faces of each groups,the averaged normals mapping will lay the UVs flat and nice...you see it's not that hard,you can finally re-attach every groups in a single mesh and re-weld the vertice.
Last step is to send the UV to a map via texporter and apply it to a material to put on the model....Voila.
remember though that this is how I would do it and you're better off learning as much as you can by yourself or by reading the manuals.
If the task seems too hard,just get Lithunwrap then
Just remember that you're standing on a planet that's evolving
And revolving at nine hundred miles an hour!