Believe me I know how hard and time consuming it can be but its really important. Food getting stuck between your teeth may lead to cavities. This will mean getting fillings which for some people may mean getting the brace off for a while (depending where on the tooth the cavity is) this will mean your treatment may take longer and most orthodontists won't be happy if you're not looking after your teeth properly.

Just give yourself plenty of time to do it, thread the floss under the wire for each tooth, if you're still having trouble ask your orthodontist for advice.