hey ishika...its very simple to upload files........
frst decide wht u want to upload and go in tht section....
for e.g _ if u want to upload any subject wise project........
go in uplaod / downlaod section......clck n whch subject u want to uplaod the project of ......thn clcik on new thread whch appears on right hand side of ur computer screen.... thn write breif details abt ur poject and thn.......clcik on uplaod project........another window will open up.....browse thru pc and give the link......and thn click on submit msg.........
u r project will be uploaded......hope u undrastnd.....still got any doubts.....u can ask....