You can cut the bridges with a very sharp knife, minidrill, dremel or with eg.
the stone disc bit
of such a minidrill - look
at this example.
Another very good suggestion is to ask a jeweler to cut all bridges for you.
The easiest way closing the connections is to use a 0,5 mm HB pencil but connect
no bridges among themselves.
Close all L1 bridges if you want to change the VCore and multiplier via BIOS
Otherway leave all L1 connections open !!!
This guide is not only for mainboards without multiplier / Vcore DIP-switches,
because sometimes it's possible to get higher multiplier settings than allowed
by your mainboard manufacturer.
If your mainboard allows all multiplier settings it's only necessary to connect
the four L1 bridges.