Ah, this is tough! Are there any chores he doesn't mind doing? Could you divide the chores somehow so that you're both contributing?
It's hard, I know - I hate having to nag my husband about that kind of stuff, but he has gotten better over time. I try and encourage us to do things together as well - for instance we cook together and once we've eaten we will clean up the kitchen together. Sometimes then it doesn't feel like a chore if we're cleaning and chatting!

I think its just a minor problem, maybe your boyfriend is intelligent in other way, most intelligent people is messy, just be patient about it as long as what he is doing will not go to the worst point of being messy like not taking a bath almost everyday or eating in dirty dishes and other unexpected attitude. All I can advice to you, much better not to push your boyfriend to act on the way you want him to be, just be thankful that he is acting naturally and not pretending to become what he is not. As long as he loves you he will change later. In a relationship it is better to give each other a space or freedom in order for the two of you to know or discover a lot from each other, because being strict or having plenty of rules in relationship will force you to pretend and hide your negative behavior. True attitude is not a problem, but having a pretentious partner will cause disaster on the long run of your relationship.

Boys are mostly messy. You must adjust for him a little then after you got his attention . Say what you want to change on him and explain why he will change it. Nice approaching is better to encourage him to change his being messy.

As for me, why not just tell him in a nice way. Keep things in order tell him where his clothes should be put on, how to properly put toothpaste, just help him to get through it sooner or later he will get used to it.

Before you decide to move in with your boyfriend, ask yourself if you can live with your boyfriend's habit. If you really love your boyfriend, you will accept his imperfections like he accepts yours. All of us has our cons and pros and your boyfriend's cons are being untidy when it comes to the house--which I think is not a serious problem. I think most boys have that nature to be messy when it comes at home. But you must also tell him what you feel or what you like or don't like; if he really thinks of your situation he will adjust and he will find a way not to upset you. You can't change a person, because you want them too, they have their own decision.