I need some advice about a serious relationship?

I think I'm on the brink of engaging in a serious relationship. This place might not be the best for asking such a question, but I haven't been in a serious relationship in a long time due to not wanting to get "burned" or "hurt" as I have so many times in the past. I think I might flake and I'm somewhat ashamed to admit I'm afraid to go through with this...what do I do?