If you do not want to waste time, find a proper reference of orthographic front and side views, there are plenty on the net; and model according to that.
In 3d, there is no issue of cheating, as professional modelers also model according to 2d model sheets. No point banging away and eternally struggling with proportions.
You are a beginning modeler, concentrate on getting your first model correct anatomically by using good orthographic references; it will boost your confidence when you later model other characters as you would understand the workflow of model creation.
Also, your current pose will be a nightmare to bone later, due to the close proximity of the fingers for example. Model them spread apart.
Having seen your reference, you are just unsure of how to model higher mesh defination for the muscles, search the 3d forums there are plenty of wireframes.
E,g.:
http://forums.cgsociety.org/showthread.php?f=43&t=190477&highlight=torso+wireframe









