There is a variety of ways to increase the charisma skill in the Sims 3 making it a fun skill to work on. The charismatic trait is a must if a Sim wishes to become a master of charisma because it will make this trait much easier to learn. Other traits also help those wishing to master this skill and will be discussed later in this Sims 3 charisma guide. There are three ways to learn and master the charisma skill: reading a book, talking to mirrors, and talking to other Sims.
Read a Book: Reading a book about charisma is the fastest way to increase this skill. The charisma book can be purchased at the book store or a Sim can head to the library and read it there. Reading it at the library is free and will allow Sims to increase this skill faster because they will get the power study moodlet by studying at the library. Buying the book will make it available at home, but it costs money so unless a Sim has some extra cash it is best to read this book at the library unless buying the book is a wish. If a Sim has the bookworm trait, they will increase their charisma skill by reading a book even faster.

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Talking to Mirrors: Like in the Sims 2, the charisma skill in the Sims 3 can be raised by talking to a mirror. The cost of the mirror does not matter and more expensive mirrors will not raise this skill any faster. This will raise this skill about as quickly as chatting with another Sim so in the end, this is the least beneficial way to learn charisma.
Talking to Other Sims: Not only will talking to other Sims increase a Sim's charisma skill, but it will also help them keep up with the charisma skill friend requirements. If your Sim wants a Sim around to chat with all day, prepare a nice breakfast and invite them over. After breakfast, spend some time watching television and chatting together. This will keep them together, and talking, for most of the day so your Sim can raise their charisma skill.