Not too late?

I've been thinking about this girl a lot lately that I've known since we're were kids. I've had feelings for her throughout my life but I've unable to express how i feel. Mainly because I was really shy. We went out about 4 years ago and we had a good time. Unfortunately, I didn't pursue the relationship further because of my self doubt. I contacted her couple years later to see if we reconnect. It didn't go as i would liked. Now I really want to see her again and hopefully start relationship and I want to fully commit this time. Any advice on how to proceed? Thank you.

Do you have her e-mail address? Ask her how's she doing. Chat for a little while. Invite her out for coffee. Talk some more and see how it goes. Then ask her out. That's how it's done.

If your last attempt at reconnecting didn't go well, what makes you so sure you want a committed relationship with this girl? And, I have to ask, what do you mean when you say it didn't go how you would have liked? If you want to go after her, that's all well and good, but make sure you're keeping both feet in reality.