Mesh problems

If I have a mesh and save it to frame one, and then go to frame 10 and change the mesh’s head so it turns, how do i set that to the frame, so if i play it , it looks like the head is turning?

Use the I-Key to insert keyframes. A popup menu will show asking you for the properties you want to keyframe.
Details can be found here: http://wiki.blender.org/index.php/Manual/Editing_Ipos

How are you turning the head? Does it have an armature, or are you using Shape-keys?

no, it has no armature as something went wrong when i was trying to add one. I am just selecting the vertices and then rotating them. By the way, what are shape keys and how do you use them?

I don’t think you can animate manually mesh deformations. You either need an armature or shape keys. Here is the wiki page that describes the different types of inimitable deformations. There is a link to shape keys on this page: http://wiki.blender.org/index.php/Manual/Animation/Deformations