First, gather the forces and explain to the young man personally. This will help you to more clearly explain the reasons for its decision, to give arguments for the fact that such a measure is necessary. In no case do not tell about the break by phone, e-mail, via mail or acquaintances. Your former favorite accurately positively not appreciate such degrading attitude. Honest, open conversation will give you the opportunity in the future to maintain warm and friendly relations with that person.
Never opt for such a serious conversation is the place where you spend a lot of happy moments - the home of one or the other, a favorite park or park, cafes, etc. Ideally, this should be a neutral territory. It is desirable to explain where you will not disturb anyone.
Do not forget to pre-rehearse all the things that you say to the guy. Spend a few hours on it, but carefully grind his speech. Please note that all your words should be as correct. Do not go to the individual, not sypte insults and humiliation - and so you have enough swearing. Try to leave politely. However, be prepared that your ex-boyfriend did not meet this news with joy. He can give you everything you think - tune to it in advance and pick up the words and phrases that will help alleviate his frustration and anger. So he will be able to feel that you care, which means that the chances to stay friends with him to grow.
Finish his first novel when not yet started the next. Otherwise it will look like a banal betrayal. And men do not like it. In addition, you risk to spoil relations with the new fan.
Even if you really do not want to part with ex-lover forever, do not say the phrase: "Let's be friends." Such a proposal men are mocking. Because for them, it is regarded as an offer, "Look how well I'll live without you." In addition, this phrase shows the man that you regret it. But this can not stand almost no representative of the stronger sex. Give him time to go through parting with you, think about your feelings. And after some time, it is quite possible, he will ask you to just be friends.