The best way to do it is to take to a gunsmith who has proper tool, hands down. A gunsmith can even tap it for choke tubes or reorient and refinish the end of the barrel all of which help you retain the guns value. If you are going to DIY whether for hobby or lack of funds research your projects, have the right tools for the job, stay in your experience comfort zone and take your time. Do realize if you make a mistake and don't take a chance if you think you've done something that might make the firearm unsafe. If there is any question of the safety of the gun have it checked by a pro with the proper equipment to test/check it out.
Keep up with the trends, avoid the fads, take your time and do work you can be proud of always