We usually said like this : 你穿多大码？ or 你穿多大码的鞋？

its correct!

你穿多大的？ni chuan duo da de? 你要多大的？ni yao duo da de ?

Sorry, the size is 码. You should ask 你穿什么码的鞋子？ And in chinese, the order of sentence is different with English. We speak like this: You wear what size of shoes... Wierd, right? That's how I feel about English too. LoL

yes, you are correct,you can also say 你穿多大号的？