I'm kinda the opposite... I am shy online (find it hard to post, always feel... Silly?) but IRL I find I'm that nutty woman who will chat to whoever I'm around. I never used to be like that, usually quite reserved, and I guess sometimes I'm still pretty shy (just depends on the situation I guess).

What I've found helps is starting with a smile. Seems silly, but as soon as you smile it seems to relax other people and then might open the way for a chat. I also give people the benefit of the doubt - what makes me shy is that I usually don't trust people, so if I think the best of people, it usually makes it easier to talk to them. Reminding myself they're normal, doing exactly what I'm doing, so why not chat if I feel like it? I do tend to have a different 'personality' I adopt when I'm feeling 'people person'-ey... Different to how I am with close friends and family etc... A bit more bubbly and confident I guess? I dunno... I feel like I'm rambling sorry.

My work helps too, I'm a receptionist, I have come to enjoy chatting with clients at the front desk and speaking with people on the phone (provided they're nice).

Mind you all that being said I guess I'm not a full on extrovert, I do find it draining to be 'on' and a 'people person' ALL the time...

Lol I hope that helps :/ maybe someone else will come along with better practical suggestions and less rambling