99% of people and their dogs have mad insecurities and are unsure of themselves. I remind myself of that fact which boosts my already high confidence. Going to the gym or all that other stuff won't boost your confidence. You should be doing that stuff for your health. Confidence is all in your head. You can bench 250 and still be an insecure person. Anyone that is new to you will have thoughts swirling in their head if they are being boring, if they look attractive or not, if they seem weird, etc. So keep that in mind and go conquer the world. Just be comfortable.
Talk to strangers and watch them look at the floor as they respond. Say a dirty sex joke (outside of work) and watch them squirm. If anyone disses you diss them back harder where it hurts ( af galooc lips, fat calool, wearing a weave). If anyone cuts you off on the road, you honk that madafoka for 5 long seconds. If someone holds the door for you, say thank you very much I appreciate it and look them in the eye. Assert your dominance.