Hi, all!
I never really used a 3D Printer before, and I want to print this model (if possible), but I know it already has a lot of errors (I have tested them on Simplify3D, MeshMixer and some browser 3D Printing testing sites to detect mesh errors). Can anyone with more experience help me about what I can do to make this model printable? Thanks in advance!
SinonSAO - 3DPrinting.blend (14.5 MB)
No answers, likely because characters that were modeled for other purpose than 3d printing are challenging to prepare for it, and it’s too difficult to explain all that needs to be done.
There are non-manifold errors in the model, most of them are open edges which means that the surfaces don’t describe a solid, but there also are interior faces because some of them were closed wrong, describing an impossible surface. There’s self-intersecting geometry, surface collapsed through itself, and also intersecting geometry that might or might not be a problem.
If the importing application can interpret intersecting geometry (such as Slic3r with its stupid name), that could help getting the model ready because all separate parts could just clearly intersect, as long they’re all manifold. Otherwise one would have to connect the geometry so you’re left with one mesh part for the outer surface. That’s assuming it’s all in one, without making some parts removable.
Optimizing the print would mean checking the tolerances, print orientation and supports, and making the model hollow to save materials and time. Those depend on what it’s printed with.
Cadspan might help to produce a printable model with less pain, there is a trial available. http://www.cadspan.com/
Thank you very much for the detailed answer! 
I’ll do some research on the topics you mentioned to see if it’s possible to 3D print this model.
Thanks, I will take a look. 