Anatomy of a Sim (The Sims 3™)

Building a good Sim for The Sims 3™ can be as detailed as you want or as simple. Often it's not always the most complex methods or the most advanced techniques that create the winning formula for a Sim that is attractive to the eye and behaves well in the game for general game play or for posing for photos or video.

Over time, my own techniques have changed as well as my eye for certain details. The Custom Content (CC) I have chosen has also changed.

So if you have an ambition to create Sims and would like to know how TheReds Studio creates a Sim then read on. There are lessons learned that can sometimes be harsh when you have to learn them on your own by discovery. These are trials and errors that I hope you can avoid.

The Base Game

The Sims 3™ game came with a number of Expansion Packs (EP's) and Stuff Packs (SP's) over the many years of its release. Creating any Sim that uses elements from these Packs will then create dependencies or requirements for these EP or SP to be present in a game.

What that means is that a person downloading your Sim will need to have that particular EP or SP Pack in order to see the Sim the same way as you created the Sim. If they are missing the Pack in their game, then The Sims 3™ game will automatically replace the missing content with a random equivalent item. That is not so bad if the missing content is something like a bracelet or earring. But if it is hair or other bodily aspect of the Sim, then the look will be considerably diminished to what you, the Creator has designed.

So be mindful of EP or SP add-ons. Try to avoid intentionally using content from these sources. Not all players of The Sims 3™ will have the required EP or SP that you use on your Sim.

Custom Content: Sim3Pack versus Package

Many Custom Content (CC) comes in either of these two formats. TheReds Studio only uses CC that was added into the base game by Sim3Pack file.

Some content such as Skin and Eyelashes come only as a Package file format. These will need to be added separately as a whole Sim created and then exported from the game as a Sim3Pack file will often be missing any content that was added into the game as a Package file. Not always, but certainly often enough that it is better to name the Skin and Eyelash used and make a reference back to the original Creator of those missing CC.

At this stage it is worth mentioning that you should always list your CC used for the Sim and reference back to the Creator for credit.

Here are some valuable tips for anyone wanting to create Sims for public download that I recommend for you:
  • Create a brand new Vanilla Game folder and install fresh copies of any CC you wish to use for Sim creation.
  • Do not mix sim3pack clothing, accessories, hair or makeup with the alternative Package format clothing, accessories, hair or makeup. Better to choose Sim3Pack format only and have no issues exporting the Sim with all the CC intact.
  • Do not add CC into this version of your game folder that is not relevant to Sim creation.
  • Keep this version of your game clean. And never ever download a Sim into this version of the game.
  • Only use this version of the game for creating and exporting Sims.
  • When you are not using this creator version of your game, then you can rename "The Sims 3" folder by adding the word "Creator" to the end of the folder name. Even add a picture to the root of this folder that visually indicates it is your Creator version of your game. You may copy and save this one below if you like.

Starting with a Base Game Sim

For this example, we will start with a Toddler Sim from the Standard base game.

Now using the in-game tools, we age her up to Young Adult and we do some basic body adjustments to get a basic form of the Sim we want to create.

The game has given this Sim a random choice of hair which happens to be a Custom Content hair. But it is not one that is good to work with when making changes to the Sim as this hair covers much of the face and head shape. That makes it hard to edit.
So we are better off to remove the hair style for one less restrictive to the view. And also change the eyebrows and skin.

Now we begin to shape the head. In this example, I have reduced the overall length of the head from top to bottom and adjusted jaw and cheek.

And now adjusting the eyes and adding eyelashes. I personally like S-Club 3D Art Eyes III Eyelashes.

And now Nose adjustments.

And now lips are adjusted.

The body is now seen from the basic form that I had adjusted earlier. I choose to adjust my Sim while she is naked. The only reason I do that is so that I am not misled by the way some clothing sits on a Sim. I use a naked Sim CC clothing by Kilhian which I understand is literally a full body transparent outfit.

 Adjusting the body is whatever you like it to be. Sometimes we idealize a particular shape and dimension to things. As a guy, I am going to prefer different things. You will have your own choices. Nothing is wrong. It is simply your choice.
Take care with third party body sliders. There are many people who make custom body sliders that are a Package file CC and again there is a doubt cast on the correct export of this type of CC with a final Sim in a Sims3Pack file. In addition to this problem, there is also an issue with a Sim that has custom body sliders where clothing is incorrectly fitting and Pose Player Poses do not correctly line up due to an extreme body dimension.

And now the hair is chosen and applied and the Sims physics are complete.



Eyes are always an important aspect to the Sim. The default eyes are replaced here with CC eyes that have far more life-like appearance.

Eyeshadow is now applied and we can begin to see more character appearing in our Sim.
I prefer a clean look to eyeshadow. Not too heavy on color or opacity.

Eyeliner is also an important aspect to the eyes. Again I like to highlight but not overpower the eyes. That little lick at outer corner is a favorite of mine.

Blush is now added and I prefer a light tone so I usually am careful with opacity level. You can see the change is subtle when comparing to the previous picture, above.

Lipstick now. Like everything else before it, what you choose has to make sense.
I am a guy. A male. I shouldn't know anything about women's makeup. And really, the truth is that I don't know. But I do know what I like to see. And this game has taught me to appreciate what women go through to choose what works and what does not. And I never had a girlfriend who shared her secrets or read Cosmopolitan or any other magazine to find out.
Your choice is your choice. Make a choice for a reason.

Finally to adding some clothes and accessories and do a final tweak of the Sim and makeup.
Take your time with this step. It's easy to get excited and skip past this. But check your Sim from all angles. Up close and also from far away. Check everything and tweak if necessary.

And finally: Always test your exported Sim in a Vanilla Game. If you are missing anything, then it will show up in a Vanilla Game.

This is Roseli!


Roseli Silva is a Signature Sim created for a friend. She is not available for download from TheReds Studio.

Final Word

Anyone can create a Sim. My intention is to not school you in how to make a Sim, but just hopefully give you some ideas to avoid the issues I encountered in my journey of learning.

In my time, nobody ever taught me everything. I had to discover some painful and time consuming issues that frustrated and made me crazy why some things failed. Hopefully you have some good ideas to help you keep your game running smooth for Sim Creation and less trouble for you and your Followers.

Good luck and be happy. This game was invented to bring satisfaction and enjoyment.

Be unique and be creative. Never ever support plagiarism and stand up in the community for protecting the rights to intellectual property.

And honor the CC Creators whose work means everything to you as a Sim Creator.

A little Bonus for you!