This is heartbreaking for me because if I continue the lie, he may accept a false me. Also I want him to accept me after knowing everything about me. I don't want to be afraid of the man I love. But at the same time, I don't want to confess because it may hurt him too permanently. I just don't know what to do. Technology today and other ways of finding things out are insane. Nothing is private anymore and stalking is too easy. This makes everything so much scarier. Hacking, talking to friends, parents, finding old addresses, anything. No one is safe anymore. He can possibly find out on his own, and, I don't want that. Like I said this is about values. I don't believe in lies and the easy way out so why should I lie. And plus he may accept a false me, and really want a virgin bride. As silly as that is to me, it's his right, and he should live the way he wants. Who am I to take that away from him? How am I supposed to start such a conversation? What I am still confused about is, he never asked me about my relations but accepts the fact that I had boyfriend(s). What exactly does that mean and show? "So, I accept you had a boyfriend yet you're still obviously a virgin!"
It is very good that you have come to the conclusion that you need to be honest and open to your future husband. This is a very wise decision because if he finds out the truth after the marriage, even if he accepts it, most probably and especially when the heat of new marriage has cooled down and the reality starts to hit, he might think that he was cheated. In other words for the rest of his life he will think that you somehow deceived him. So yes, definitely letting him know just now is the best choice. It is also his right to know this before marriage.
As for how to say it, well, it depends on the cultural background and the personal circumstances and I am sure you appreciate that I cannot give you any prescription and specifications while I am not and cannot be aware of any of these.
However it makes sense to say that a word that comes from heart, settles on heart. It seems to me that if you talk to him with all honesty making it clear that why you need him to know this at this stage rather than later, and if you make it clear for him that you are sorry about what had happened and that it was a mistake and you have repented from that mistake, then by the will of God he will see this with a positive view. I don't think expressing your concerns about whether being virgin is important or not will help here. You need to understand that for him; not being a virgin might be an indication of some moral deficiencies. You need to assure him that this is not the case and that this was a mistake that happened when you were not mature enough.