category list order

can someone help me please, I am trying to use the wp_list_categories command on my footer, i need the list to be in specific order, not ascending/alphabetical, either i have to somehow change the id of the categories or somehow order the list,
order by id should be: 10,12,13,7,8,11,9
i’m new to all this php/css so i’ve looked on the support pages and tried a few things but nothing gives me the result i want…

I have lots of other issues but i will hopefully manage to sort them out myself, i’m trying to rebuild a site that was set up as html and convert it to a wp blog so that it can be updated very easily by a few different people and only the content will change, not the design!!