Sims 4 CC/MD/Blender help

Hi. The abundance of ~1 hour long start-to-finish tutorials fools many people into believing that everything they need to know can be covered in such a short amount of time, so they never try to go beyond that, and that is the worst thing they can do for their progress. In reality, you cannot learn or teach various 3d concepts, how to utilize 4 programs, create and adapt custom content in one hour or one tutorial, so you won't find much  in-depth information on these matters in ts4 themed tutorials or forums. I also do not recommend you to look for guidance in this from a specific person because trying to learn how to set up the render or materials from a text post is a waste of time, you need to watch a video with proper explanation. Also, I've seen how meshes from top creators in our community are made ( we have people coming here asking how to fix them), let's just say, you do not want to pay those people to teach you how to make mistakes unless your priority is quantity over quality ( no time to improve, patreons won't update themselves, you know).

Only one of your questions is exclusive to ts4, so if you want to receive in-depth info or assistance for the rest, you need to seek them outside of this forum (this is the s4s-themed forum after all) or, better, ts4 community. After that you can make something simple, bring it here(better in the discussion section) and we can check if there's anything wrong with that

- click on the avatar, in the properties panel to the right there will be something like smooth avatar. Bear in mind this will create holes along seams, so before importing an avatar in s4s, remove doubles in blender;
- clone an outfit that is meant to function the same way as yours and transfer the data from it. The less sculpted details the reference has, the better. Making pants? use nude lower body. Making a skirt/dress? use a skirt/dress of the same length. Your top does not go below the navel or in the head area? Transfer everything from the nude top, etc;
There are only two vertex colors meant for clothing: 3FFF00 - for the skirts, 00ff00 - for everything else;


- bake diffuse textures with cycles, use high-quality mesh for baking and low-quality for the game. To know how, watch a tutorial on rendering and baking with cycles that is not centred around ts4. Ideally, you'd want to know how to add lights,too;

- it would be a better idea to set up materials in Blender instead of editing baked textures. For that, watch an introductory tutorial for materials/node editor;

- watch introductory tutorials for those programs as well

so yeah, it is best to receive this information from people who know those programs good enough to make introduction videos for free and have hundreds of thousands followers on youtube

In our case, it is more a matter of the lighting setup. The environment in ts4 is static and reflections appear only on the higher settings, so we need to fake an interesting(but not too much) environment so that the diffuse texture does not look too flat.
For example, if you will bake an ambient occlusion map for a ring and make it yellow in photoshop, it will not look like polished gold. But if you will introduce one single source of light and tweak the roughness of the material, its reflection will make it look more like gold. If you will leave roughness as is, it will still create a lighter area that makes the texture look more complex.
Playing with nodes is helpful when you’re making something that has a pattern/texture. For example, there is no point in assigning a (regular) cotton texture to a t-shirt because the uvs are so smalll, none of those details will be preserved. However, if you will assign a leather textures, including roughness and normal maps, you will get, well, a noisy image (as in, all the details cannot fit in one pixel type of noisy, not poor quality) but it will be noisy in a way that make sense. Here you can see there is lighter graininess in the right places that makes the texture look more like leather rather than rubber.

THAT if you have the direct source of light in the scene.
Another useful thing is projecting patterns and logos evenly even if your uvs are stretched.
For example, you made a t-shirt in md that is tight and stretched in the chest area. If you will put a logo on that area, it will be stretched. You can create a second uv map, unwrap the uvs so that there is no stretching, put an image where you need it to be, then bake that texture from this uv map to the original.

But let’s get back to the lights. If you were to study maxis meshes, esp shoes, tops and anything shiny, you would be able too tell that those are not ambient occlusion maps. There is a key light coming from the top, then there are fill lights that remove harsh shadows that the key light would be casting otherwise.
In photography there’s also a rim light, but we would not need it in this situation, there’s just another source of light in the back.
Anyway, this type of info should be covered in any introductory tutorial to lightning in blender, so you do not need to go into photography