Help with UV Mapping and Texturing

Hey Guys!
I’m working with High poly models (REALLY high) in Blender and I need help with UV Mapping. I’ve checked out tons of Tutorials via youtube but most of the models the makers make have sometimes less than 10% the Poly count mine do. I have tried decimating but it hardly makes it easier and ruins the edges. While I don’t mind losing quality, I would at least like it to be simpler.
Is there anybody here who can teach me how to do so in Blender? I’m really struggling with UV Mapping and I really need help. If you can, please contact me either here or at Thanks so much for helping out!

If it’s too high poly then you need to retopologize, that’s something you have to do by hand, because automatic methods don’t usually work well.

In edit mode select edges along with you want the model to be cut then press ctrl + E and chose mark seam, After you done with marking seams, select all (in edit mode) and press U then chose unwrap

How exactly much the polycount ?
If it is half million or something it will simply not suit for gaming.
If it is really complex object that needs much polygons, you should model it piece by piece and none of piece should be more than 150.000 triangles.(not quad)
Other than that, you should retopologize it manually(not automatic) and with normal maps, heightmaps or something you should transfer details, search for tutorials about it.

can you post a pic of your mesh? it would be easier to tell you how to make it simpler.

in most cases your right but in some games like forza 5 the cars are around 500K tris in game (around 1mil on the vehicle select screen) so it depends on the model/game and platform.

Wouldn’t those 500k tris be divided into many separate pieces like the hood, trunk, glass, each door, each seat and interior piece, and even the parts making up the brakes and visible under carriage and all mapped separately like caner_ozdemir is suggesting?