Ugh I feel you and that is rough! It’s hard because everybody has different standard of messiness. Sometimes it simply comes down to a skills issue. Hard to know but honestly it’s not for you to figure out, that’s for him!
With that being said, since this is your friend, I think that you should be open with him about how you feel while also making it clear you want to work together to figure something out. I’ve done chore charts with roommates in the past and that really worked out well. I think it’s important that you have some things in mind but also make it a collaborative effort so he doesn’t feel like you are just putting these demands on him. He will be much more likely to follow through if he helped create it.
I suggest also being very clear with yourself (and him) about what things are most bothersome for you that you really need to have a hard boundary around, and what things you can let slip. I say this because if you are giving that same energy to everything it is going to make things emotionally difficult for you. if he has been living this way thus far, there’s going to be a margin of error here. So I wouldn’t necessarily share what the less important things are, but the most important things.
This is going to be an ongoing process. You might find that some things are working really well and other things aren’t, so you come together to figure out how you can adjust to make it work better. I do think that this conversation really needs to happen though because resentment can build up really easily, especially if you’ve mentioned it before and nothing has happened.