When you meet someone for the first time, they have absolutely no idea what you are like to hang out with. If you have been shy and timid your whole life, the best time to come out of that shell is when you meet someone new. If you are at a networking event and someone walks up to introduce themselves, your old self may have quietly shook their hand and looked down in embarrassment. Why not use the opportunity to develop a new persona?
Instead of being shy and timid, greet the person with a big smile. Look them in the eye and project your voice with confidence as you say your name. Have an interesting question prepared that immediately gets the person engaged. Instead of asking what they do for a living (the standard), ask them what their favorite restaurant is or ask them about a hobby they are passionate about. Let their enthusiasm to share their passion enhance your confidence level and energize your own enthusiasm.
If you practice this often enough, you will eventually become that new person and you no longer have to practice. It will be who are ARE!