IMPORTANT: Please, if you want to use icons from PRO version in Bootstrap, be sure you don't violate the license. Icons (except Halflings) are not provided for free and GLYPHICONS license is not compatible with most of the open-source licenses.
TIP: do you want to have all icons pixel perfect (or let's say almost)? Try to set their basic size to 24px (12px for Halflings) or their multiples. As you can see on this page, when icons are smaller or in atypic size, they are blurred. If you're not sure which files exactly copy and where, just explore this HTML, its header and files in this folder. Remember, this is just an example, have a fun!