Read how to win friends and influence people, but in the event you don’t:
Charisma is your ability to get people to do things you want them to do, roughly speaking.
1. Smile and act happy as much as possible. All the time. Why do people love dogs? Because they’re always happy to see people. This is amplified a bunch if you’re actually happy to see people, but it’s possible to fake it (a la Patrick Bateman style).
2. Have a lot of energy, be willing to do things purely for the sake of helping others.
3. Don’t criticize, and more or less ignore bad things in the world and focus on the good. People don’t like downers, and would rather hear a flattering lie than an inconvenient truth (no, your ass never looks fat sweetie)
If you do these things but are a scrawny hunchback with crooked teeth people might enjoy your company but will never be ale to truly respect you, so if you want to go for the very top of the charisma chain you need to take a lot of care of every aspect of your body, so get ready to get /fit/.