It’s okay to talk about yourself if it’s to help somebody understand your point. You’re using your experience as an example. Because then you’re not really talking about yourself. And because you’re focused on making your point, and because it’s relevant to your message, neither you nor your audience will take it the wrong way.
It’s not okay to talk about yourself if you’re trying to impress people with how wonderful, intelligent, accomplished, special you are. You’re focused on yourself and so will they be. You won’t be invisible, you will be uncomfortable, and so will your audience.
When you’re clear on the difference you won’t be so reluctant to use your experiences to liven up and drive home your message.