You are obviously aware that the distance has the potential to wreak havoc on your relationship, and have already indicated in your post that you have no intention of breaking things off with him, so I'm not going to give you the usual "don't do it" bit.
First, you need to know and believe that it's totally possible to survive a long distance relationship; I did it myself for several years and am now engaged. It's obviously difficult and emotionally taxing, but if you go into a LDR with doubts, or constantly question whether or not you'll be together in the end, that negativity will slowly seep into the foundation of your relationship and it will fester. Don't even bother thinking about what may or may not be 5-6 years from now; you're not Miss Cleo and you'll only drive yourself crazy trying to predict the future. Keep focused on your relationship in the present--enjoy it for what it is now, and nurture it now to enjoy it later. It really is that simple.
You also need to communicate. A lot. No matter how much work I had on my plate, 11:00p.m-1:00a.m each night was reserved for my guy. The scheduled conversations not only gave me something to look forward to each day, but it also helped me keep focused on my studies because I knew that I needed to finish my daily tasks by a certain time. We obviously didn't restrict ourselves only to this time frame--things do come up every now and then--but we tried to stick with it as much as possible. Sometimes, we would plan to do the same activity, such as watch the same movie, or read the same book, so that we could keep our conversations fresh and interesting. This also helped to detract attention away from the fact that we couldn't be together.
Speaking of communication, be self-aware, flexible, and forgiving. Miscommunications are bound to happen when your only means of connecting is through e-mail, phone, skype, etc, and it is all the more easy to allow that miscommunication to turn into a lover's quarrel. Be aware of your words, and always keep in mind that the LDR is difficult on BOTH of you, not just you, so do what you can to also understand your partner's needs. Remember: we all want to be right, but the only way to have two winners is to compromise.
Visit often, and just enough. The first days of a visit are awesome. The last day sucks. The last day can suck a little bit less if you know when your next visit will be. Plan your visits so that you can see your partner regularly, but don't go broke or sacrifice your grades as a result. My partner was on the west coast while I attended school on the east coast, so tickets were several hundred dollars each visit. I tried to visit once a month, which worked out pretty well for us. There was one semester that I wasn't able to go home at all until the end of the term, though. That was a really, really, tough semester to get through.
Be committed. This is a no brainer, but you both need to be on the same page and committed to the relationship. Discuss, set, and mutually agree upon the rules and expectations for your relationship before you leave.
Lastly, be mentally prepared for the possibility that this may not work out. Every relationship has the potential to fail, but the added stress of LDRs inreases the likelihood. If you're going to go forward with an LDR, you need to understand and accept that your partner (or you) can walk away from the relationship at any time, for any reason. There is no way that you can prepare for this, and there is no way for you to know whether or not this will happen to you. But the sooner you accept the risk, the sooner you can get on with enjoying the relationship for what it currently is (this goes hand-in-hand with my first suggestion).
Hope this helps. If not, you're certainly free to ignore it