Moving with kids! Need some tips mommies!?

I have never moved with my kids yet. We are getting a new apartment (bigger) and i am going crazy just thinking about all the stuff i need to do. Any tips to make it easier? I also want to know, what will be ok being stored in the basement? Right now we have an awesome walk in hall closet i use for the kids storage, things they are not using, toys, old clothes, and even new clothes they haven't grown into yet....stuff like that. I am afraid to put stuff in the basement because of mold and mildew, etc. Now i'll forced to use the basement storage and i want to know what kinds of things will be the safest down there and what things i need to find room for in the apt. How early should i start packing? The first time i moved it was from my parents house lol so i didn't have much to do! Any tips at all would be great!!