TUTORIAL: Combine Package Files to reduce Lag

A lot of package files lag your game and you will end up having very long loading times. The game does not seem to care that much how large the files are but does care about the number of files.

There is a method to combine them, instructions can be found here: Tutorial - Combining Packages to Ease Lag and Load Time or here: How to Merge CC Files to Decrease Lag and Make the Game run faster Guide

A few things you should and should not do

• Don't combine Hacks/Mods. They need to be checked/updated with every patch
• Know what's in the combined files. Keep a Excel Sheet or something so that you know what is where when you need to get rid of something
• Don't delete the original files. You will need them again, if you want to get rid of stuff. There is no 'uncombining' 

Further Reading

• BUG: Lags & Intermittent Freezes 
• Game Help:Package File Lag 
• Game Help:Improving Sims 3 Performance 

TUTORIAL: Sims3Packs to Packages

To convert Sims3Packs to Packages you will need Delphy's Multi Sims3Pack Extractor.

Installation
Installation instructions can be found in the Overview page of the tool

Usage
Copy all sims3pack files that you want to convert in a folder of your choice (in the picture X:\Sims). All files that the tool finds in this folder are being converted automatically. To set this folder in the tool choose browse in Step 1.

In Step 2 you can choose where you want to extract your files to. I recommend to choose another folder than the mods folder to extract the files to (in the picture X:\Sims, too)

Now you have to decide what you want to name the package files. You can name they way they are inside the sims3pack file. These are cryptic names. To do so, check the option rename file on save. If you do not check the option, the package files are named the same as the sims3pack. This is only true if there is only one package file inside the sims3packs. Houses and Sims have more then one most of the time.

Now click on Extract and you're done.

Now copy/move all files you want to keep to the Mods-Folder.

To convert package files to Sim3Packs you will need TSR Workshop but I have no clue about that.