How to maintain a long distance relationship？

well,I need help.

There isn't enough context in your post to furnish you with even a vague horoscope's worth of advice.

How long have you been in a relationship?
What's your respective ages?
How serious were you prior to him heading (assuming its college) off to study in another state?
When was the last time you saw him in person? Was there a viable spark during that time? Any significant changes in the relationship?
What do you plan on doing in the near future? Schooling wise? Life wise? Career wise? What about him? Do these plans actually overlap?

Long distance relationships are difficult, but not impossible so first of all, you need to ignore all the negative comments that you're going to get about how it's "not going to work out". Next, communication and understanding are two key components to a long distance relationship. A lot of people are saying phone but in all reality it's difficult and expensive. Try sticking to the free options such as skype, facebook chat, yahoo messenger etc. If both of you have smart phones you can both download the skype app and use that to keep in touch while you're not at your computer.

Lastly, there has to be an end date. You have to know that eventually, the relationship is not going to be long distance. And whether it's a specific day down to the minute or if it's just a general time, the two of you need to discuss how and when that is going to happen.

Good luck, it's difficult at times, but it's worth it