Take a look in the removal section of the forum. There is a great list of tools you'll need (or may need) for the job.
Basically, wear a suit and gloves. Do what you need to expose the hive, then carefully cut out the brood comb and rubber band it into empty frames. It helps if you cut from the bottom of the combs in frame-sized heights. If you can't access the combs very easily (ie, you opening is edge on), removing outer combs first, which are likely to be honey storage, will give you room to maneuver at the brood comb. Scoop or brush out loose bees into the box. Try to find the queen.