Mass upload Accounts and Contacts from Microsoft Excel into C4C

Hi,

I would like instructions on how to do the following this in excel and upload to C4C. Please include links whenever you can instead of mentioning the title of a page I need to go to, I often can't find those pages on my own. Also, please let me know whether I need to be in Administrator or not. Thanks!

1. Mass uploading Accounts from Excel
2. Mass uploading Contacts from Excel
   1.     We also need to know how to either a) assign a contact as also a lead or b) either mass upload leads or select a large group of contacts at once and label as leads. I prefer option B so I don’t have to individually label each contact as a lead like in option A