Dont have the proper training or paperwork and then owe the IRS like 10k and then ask Obama to cut your taxes..--Answer1:First you should get a tax id number and a Business license for your city. After that buy the basic tools required. PRINT up flyers and pass them out in neighborhoods in your city. It will take some time and business will come word of mouth is the best form of advertising so talk about your business alot people will try you out..--Answer2:If you have your plumbing license you can start by doing the paperwork to fill for an LLC, Corp, or a sole proprietorship.If you dont have your license, then get an apprenticeship. Honestly, the best way to learn how to run a successful business is to work under a successful business owner for a while and learn from the mistakes and successes.If youre striking out, learn some basic accounting, have a decent amount of starting capital, an established line of credit with some wholesalers, get a phone number, take out an ad, and work on some contractors in the area to network and build a relationship. Talk to a lot of landlords in the area, anybody who has property. Starting out you really cant turn down anything - its a very competitive business when the housing markets down. Work your *ss off.