There are countless tutorials and resources online to assist you with creating your 3D file. Your software wiki page and forum pages may be a great help. Look for tutorials about making your model watertight and preparing your file for 3D printing. Ask a friend or the Help Desk in Rettner 201 for assistance.
The Digital Humanities Center, located in Rush Rhees Library G-122, holds workshops on how to use 3D applications like Blender, Fusion360, and Sketch-up as well as general 3D printing principles and best practices. More information and a schedule of workshops are available on the Digital Humanities Center website.
Guide to 3D Printing is a must-read if you are unfamiliar with 3D printing process. There are many different types; currently Rettner 201 only offers Fused Deposition Modeling (FDM)/Fused Filament Fabrication (FFF).
Additional recommended online resources: